BOSS KEAN: Sorry, Luke, I’m just doing my job. You gotta appreciate that.
LUKE: Calling it your job don’t make it right, Boss.Donn Pearce (1928-2017) American novelist, screenwriter
Cool Hand Luke (1967) [with Frank Pierson]
In the actual final script, the exchange goes:BOSS KEAN: Ah'm jus' doin' mah job, Luke. You gotta appreciate that.
LUKE: Boss, when you do somethin' to me you better do it because you got to or want to ... but not because it's your damn job.
Quotations by:
Pearce, Donn
What we’ve got here is a failure to communicate.
Donn Pearce (1928-2017) American novelist, screenwriter
Cool Hand Luke (1967) [with Frank Pierson]
(Source)
The line actually occurs twice in the movie. It's initially voiced by the Captain, the warden of the prison where Luke is sent to. While the line shows up in the final revision of the script (sc. 313) as above, Strother Martin actually speaks it in the movie without the indefinite article "a" before "failure":
What we’ve got here is failure to communicate.
The second time the line shows up -- spoken by Luke, at the end of the movie, mocking the Captain -- it is both scripted (sc. 432) and filmed with the article intact.