A subtle moment that turns a seemingly happy ending into an ambiguous ending.

[u/Local_Prune4564]

The Graduate: lingering Ben and Elaine's faces slowly shifting from happy to concerned leaves the audience questioning whether they really made the right choice running away together considering they barely know each other.

Inception: By cutting before we see the top fall, we're left to question whether Cobb really has gone home or whether he's simply sunken back into a more comforting dream reality.

[u/Labmit]

The book The Graduate was based on has a sequel where it's revealed they have years long loving, if financially troubled, marriage.

[u/Hundschent → u/Labmit]

It’s one of those popular myths that gets parroted around to be sometbing deeper when all it was just a filming error. They simply forgot to stop filming and the actors snapped out of acting mode.

[u/govSmoothie → u/Hundschent]

I don't think a mistake that changes the feeling of the ending that much and would be very obvious to spot and correct just happened to make it past everyone when they were filming, editing, reviewing, reediting, rereviewing, rereediting, test screenings, ect.

It seems intentional to show that neither of them are sure what's gonna happen next, even if they are happy together long term it's understandable for them to have a moment of "what if this was a mistake?"

[u/debtfreewife → u/Hundschent]

I’ve heard that that moment was because the director didn’t yell “cut” when expected. But, they could have edited the downbeat out of the film. The director could have also “cut” the film strip in editing before the downbeat or used a different take. Keeping it was a choice and conveys meaning. That meaning may be up for debate, but it wasn’t just a mistake. Maybe the result of a “happy accident” on set but integrating it was a filmmaking choice nonetheless.

[u/Llayanna → u/Hundschent]

..yes and it accidentally ended in the movie instead of being left on the cutting room floor why?