Many people look at the job of an actor and think it is a ton of money for little in the way of difficult and tedious work. The problem is, most of them have no idea what percentage of actors actually make it big and bring in decent paychecks. Overall, for the vast majority of people in the field and those who are just starting out acting is among the lowest-paying professions out there. In fact, a new beginner may earn under $30,000 per year or as low as nothing if they are unable to find jobs.

In short, acting isn't nearly as glamorous as most people have been led to believe. The circumstances of the job can also be a major headache. One may be required to do their job in the elements. So rain, wind, snow, intense heat, and of course, costume and makeup work can be unpleasant when said processes may take hours. Of course, people who get into this line of work can be emotional, and many sets, whether TV or film, can get rather emotionally heated. Would we call it a hostile work environment? In some cases, yes. Of course, there are also some directors for whom a performance will never be good enough.

Finally, and perhaps most importantly, there are those pesky lines. Even for a single scene, there may be pages of writing, and an actor may need to have memorized entire paragraphs worth of dialogue while in character. Depending on the production, actors may have single short lines. Or, it may be the opposite, with long drawn out monologues that can take a while to get right. Directors range from ruthless to accommodating when it comes to actors memorizing their lines and improvising. Similarly, some actors are brilliant and can get their lines right all the time, while others have been known to need some help. On the other hand, there are those performers who have gone off script and made iconic cinematic moments while doing so. Here are eight actors who have had trouble with their lines and seven who don't even need a script to make things happen on screen.

Tom Cruise (Trouble With Lines)

There are plenty of stories out there about Tom Cruise, and we'll steer clear of any of the weird stuff and stick to a tale about his work on 1990's Days of Thunder. The film introduced audiences to Cole Trickle, a driver who is new to the NASCAR scene. While it is an exciting film and not a total waste of time, the critics bashed it as "Top Gun On Wheels" when it came out, and that criticism is fairly accurate.

Interestingly, however, the script was rewritten several times during the filming process, which led to some difficulty on the part of Cruise. In particular, while he was doing driving scenes, he would often mess up his lines. He initially tried to tape pages of paper with his lines on them to the dashboard, but wrecked a car trying to read and drive at the same time and decided to get fed lines through an earpiece for those scenes instead.

Johnny Depp (Trouble With Lines)

It is hard to tell if Johnny Depp is a case of "not remembering lines" or just never bothering to learn lines. He's played some of the most memorable characters in the history of film, including Jack Sparrow and Hunter S. Thompson (or Raoul Duke if you prefer, "I'm a doctor of journalism, man"), but a couple of years ago his former management company claimed, in documents in a lawsuit, that he never learned his lines throughout his career. Depp was suing them because he said they mismanaged his money, and they counter-sued, claiming his own spending was to blame for his financial situation. In the suit, The Management Group (TMG) claimed that for decades of acting work, Depp had been using an earpiece and employed a sound engineer at all times to feed him lines.

Rita Ora (Trouble With Lines)

Singer and actress Rita Ora is primarily known for her voice, but she's had a few notable acting jobs including the role of Christian Grey's sister, Mia, in the Fifty Shades of Grey trilogy. While she made it through filming, she listed a couple of difficult aspects to working on that project. It was the largest production on which she had ever worked, and while the simple act of just learning the lines wasn't particularly easy, her biggest problem was having to remember to stay in character, know her lines, and of course, speak in an American accent all at the same time. She admitted that throughout the filming process, an earpiece was necessary in order for her to get through many of her lines. Even though that character wasn't a major one, Ora still had difficulty getting her lines right initially, and claimed to have frozen and forgotten even her brief lines during filming.

Richard Dreyfuss (Trouble With Lines)

An icon of film and television, Richard Dreyfuss has been acting since the 1960's but his schedule has slowed down considerably in recent years. Throughout his illustrious and impressive career, he has won numerous awards for his work. But that didn't stop some controversy after the opening night of Complicit, a play directed by Kevin Spacey that was debuting in London back in 2009. British critics were infuriated at the sight of a wire they saw going down the back of his neck, with one such critic arguing that "performers who cannot remember their lines should not be on stage." Perhaps wearing such technology isn't the most professional thing a stage performer can do. But in Dreyfuss' case, he was used to TV and movies, and perhaps the use of some help was as an insurance policy rather than a crutch in this case.

Bruce Willis (Trouble With Lines)

This likely goes without saying, but there are some significant differences between stage acting and working on a movie. One of the most significant is that there are no multiple takes when you're working in a play. For a film, one can make a mistake and try again. On Broadway, if you try that, your career will be very brief. Bruce Willis' first Broadway play was Misery, based on a Stephen King book and a film featuring James Caan and Kathy Bates. The story is an eerie and unnerving one—about a novelist who is essentially held prisoner by a crazed fan.

Willis was almost universally panned by critics for his performance, which seemed lackluster, and for the fact that it was widely publicized that he didn't memorize his lines and used an earpiece for the production. Some have said he had difficulty with his part, but others just said he never bothered even trying to learn his lines.

Lindsay Lohan (Trouble With Lines)

If you ever need a reason to stop doing "nose beers," look no further than a before-and-after shot of Lindsay Lohan. Similar to her aesthetics, her acting career did a nosedive when she started partying too hard. She had made a name for herself as one of America's Sweethearts, and in the early 2000's, there were few women as desirable as her. And then, the parties and cocaine started. Around 2006 and 2007, she started showing up for shooting late (and sometimes not showing up at all) and was forgetting lines with unprofessional frequency.

In 2014, she scored a role in a London stage production Speed-the-Plow, but forgot several of her lines and had to be helped through the duration of the play. What is the difference between lines in a play and lines of cocaine? Lindsay Lohan would never forget her cocaine.

Al Pacino (Trouble With Lines)

While some actors can't remember lines because they're tired from a coke binge, and others just don't care to bother memorizing anything, some do try but end up having difficulty. In the case of Al Pacino, it may be old age. Nearly 80 years old now, he was the star of the Broadway show China Doll, which opened back in 2015. And according to many who saw the play, it was awful, and Pacino had no idea what his lines were throughout. He not only required the use of what spectators thought was an earpiece, but also several teleprompters positioned all over the set to help him.

This may seem odd, as Pacino has delivered some of the most incredible lines the world of film has ever seen (think Scarface and the "Inches" speech from Any Given Sunday, among many others), but whether he just got used to learning lines for film or going off-script or is just having some memory issues, it isn't too surprising.

Michael Gambon (Trouble With Lines)

Irish-English actor Michael Gambon has been acting on screen and in film since the mid-1960's, rarely taking a break and continuing to take on new jobs to this day. Since the early 1960's, he has also been active on stage, with appearances in dozens of major shows. The current movie-going generation likely knows Gambon for playing Albus Dumbledore in the Harry Potter series, a part he took over after the death of the original actor of that part, Richard Harris.

Gambon stopped appearing on stage a few years ago after he realized he was having increased difficulty keeping track of his lines. While he maintains an active career in both television roles and on the big screen, he said that for the purposes of live theater, he no longer wanted that kind of work because he wasn't comfortable with the idea of either an earpiece or taking extra help from other people on set. He told an interviewer, "This can't work. You can't be in theatre, free on stage shouting and screaming and running around, with someone reading you your lines."

R. Lee Ermey (Doesn't Need A Script)

If you're not into war movies, you may not know this name, but R. Lee Ermey played Gunnery Sergeant Hartman in Stanley Kubrick's epic Vietnam War movie, Full Metal Jacket. He was a military veteran and had served as a drill instructor in the Marine Corps before getting a couple of jobs on other movies, including playing one of the pilots in Apocalypse Now. Kubrick hired Ermey to work on Full Metal Jacket, originally intending him to instruct an actor in the fine art of shouting at military recruits. Ermey then demonstrated his own ability to carry out this task and was told to write the scene himself and improvise as he saw fit. This movie has some of the most painfully funny quotes in any war movie, and they all come from Ermey, who would go on to lend his acting and voice to many films and TV shows.

Robert De Niro (Doesn't Need A Script)

There aren't many actors out there with more skill than Robert De Niro. If he's in a movie, chances are it will be good, and his performances have been excellent since his debut back in the 1960's. He's been in more movies than we care to name, but some of his best roles have been tough guy parts, including crime movies such as Heat, Casino (both made in 1995, a very good year), and Goodfellas. Some of his best work in the 1970's included The Deer Hunter, a troubling look at the Vietnam War, and of course, Taxi Driver. This Martin Scorcese masterpiece featured De Niro as Travis Bickle, a young military veteran with some possible mental health issues and a particular disgust for the moral decay he sees in New York City.

In the film, Bickle talks to himself in a mirror. The scene is partially meant to draw attention to his mental state, and with his own improvisation, De Niro knocked the brief scene out of the park, exclaiming with a bit of insanity in his eyes, "You talkin' to me? You talkin' to me? You talkin' to me? Then who the hell else are you talkin' to? You talkin' to me? Well I'm the only one here. Who the f**k do you think you're talking to?"

The script only said that the character talks to himself, the words and the intensity were all De Niro's work.

Matt Damon (Doesn't Need A Script)

In the late 1990's, Matt Damon was quickly skyrocketing in fame and becoming one of show business' biggest names. Saving Private Ryan was the biggest movie of 1998, ranking among the greatest films ever made. And while Damon only had a relatively small role in the movie, one scene in particular showcased his abilities on screen.

Prior to the final assault on the town, Private Ryan (Damon) has a conversation with Captain Miller (Tom Hanks) in which he remembers his brothers who have been killed in other theaters of the war. The story itself details a memory in which one of his brothers is caught fooling around with a less-than-attractive girl. The scene was improvised, and Steven Spielberg liked the scene so much that he kept it for the final cut.

Marlon Brando (Doesn't Need A Script)

Like quite a few on our list, film icon Marlon Brando often just wouldn't bother to learn his lines prior to filming. He has been called one of the worst actors to work with in the history of the business. Aside from having a serious attitude problem and often showing little (if any) respect for directors, Brando's copies of scripts were often untouched. He infamously almost destroyed Apocalypse Now by showing up overweight and with next to no interest in the project. Furthermore, he knew very few of his lines for his monologue at the end of the film. Amazingly, that final scene became a treasured moment in cinema history and while Francis Ford Coppola nearly went insane when an obese Brando (the role of the Colonel called for a fit man, in further contrast to the original novella Heart of Darkness in which that same character was emaciated) showed up without knowing any of his lines, the movie ended up having a very interesting thought-provoking end.

Jack Nicholson (Doesn't Need A Script)

There aren't many actors who have played crazy better than Jack Nicholson, and there is no example more impressive than his gradual mental decay as Jack Torrance in The Shining. He also improvised many of his lines and much of his body language while making The Departed, and throughout his acting career, many directors have let Nicholson give roles his own spin and edge. His most famous unscripted contribution to film was his infamous line "Heeeeerrreee's Johnny!" from The Shining. 

While chasing his wife Wendy (Shelley Duvall) with an axe, he manages to chop a decent-sized hole in the door behind which she is hiding and yelps his infamous and unplanned line. It was an instant hit and connected to the times, as it was a referenced Johnny Carson, who hosted The Tonight Show in those days.

Joe Pesci (Doesn't Need A Script)

Despite standing about 5'4", Joe Pesci made a name for himself as a vicious tough guy in the 1990's. No scene showcased his ability to show rage and fury quite like the one in which he butchers a man with a pen in Casino. Of course, if you watched Goodfellas back in 1990, you likely remember the scene in which he asks Ray Liotta's character, "How the f**k am I funny?" It starts out with Tommy Devito (Pesci) telling a story to a group of mobsters. When the story is over, Henry (Liotta) quietly lets Tommy know how funny he is, which is where the scene gets awkward, as Tommy seems offended saying things like "Am I a clown? Do I amuse you?" Eventually, after getting Hill to squirm for about a minute, he starts laughing and exclaims he was joking around the whole time.

The scene was based on a story Pesci had told from his youth when he worked as a waiter; he told a "wiseguy" that he was funny, to which the man took offense. Martin Scorsese instructed Pesci and Liotta to make this story play out in the film and told nobody else on set what was going on so that they would look shocked. It worked.

Bill Murray (Doesn't Need A Script)

Actor and comedian Bill Murray is incredibly skilled at his craft, and there is no actor out there (this is debatable, but it's tough to deny) who can improvise like him. Ghostbusters and Caddyshack both demonstrate that Bill Murray has no need for a script. He did plenty of improvising in Ghostbusters, but his work as Carl Spackler in 1980's Caddyshack was as twisted as it was brilliant and hilarious.

While he was given some direction, including pretending to be a child narrating their own round of golf for the "Cinderella story" scene, the words and the actions, like destroying flowers with a rake, simulating hitting golf balls, were all Murray's creation. More of the same can be said of his brief discussion of his time caddying for the Dalai Lama, so he's got that going for him.

While this show business legend has worked with scripts before, he really has no need for them.

Sources: The National, Independent, The Guardian, News.com.au, CBS News, Business Insider, New York Post, NY Daily News