Diminishing Returns Meaning

(idiomatic) A condition in which additional inputs into an organization, project or process produce progressively fewer or lower-quality additional outputs, and may, in extreme cases, cause the total quantity or quality of outputs to decrease.

Example: 2012 May 15, Scott Tobias, “Film: Reviews: The Dictator”[1], The Onion AV Club:
  Brüno was a case of diminishing returns, intermittently amusing but not nearly as bracing or funny as Borat—it didn’t help that Brüno was the most thinly conceived of all his Da Ali G Show characters—and the lead-up to Baron Cohen’s new comedy, The Dictator, made it look like he’d boxed himself into a corner.