I’m told this terms also applies to non-screenwriting professions. To some extent, genre dictates possible endings. In Derek Rydall’s “I Could’ve Written a Better Movie Than That!”, four endings are identified:
HAPPY ENDING
The protagonist achieves their “outer” and “inner” goals. In other words, the hero gets the gold and becomes a better person. This is almost a given in romantic comedies. In “The Back Up Plan”, Zoe has her baby (twins) and a man who’ll stand by her.
BITTERSWEET ENDING
The protagonist achieves their “inner” goal, but fails to achieve their “outer” goal. In “Rain Man”, Charlie doesn’t acquire “ownership” of his brother, but he does grow from a self-centered narcissist to a more selfless brother (metamorphosis). In “Little Miss Sunshine”, Olive Hoover doesn’t win the beauty contest, but brings her family closer.
CAUTIONARY TALE
The protagonist achieves their “outer” goal, but fails to achieve their “inner” transformation. In “Citizen Kane”, Charles Foster gets the power and wealth (outer), but dies empty and unfulfilled. Fables are moralistic tales warning what happens if you don’t follow a certain moral code.
TRAGIC ENDING
The protagonist achieves neither their “inner” nor their “outer” goal. “Leaving Las Vegas” was a tragedy because he drank himself to death. Hollywood avoids such endings like the plague. Audience desire some sense of achievement in their films. Perversely, “Romeo and Juliet” and “Thelma and Louise” technically don’t qualify as tragic endings because Romeo and Juliet ended up together (albeit in death) and Thelma and Louise were emancipated from their dreary lives.

TerranceTheTrailerTrasher
March 27, 2011
“Back Up Plan” sucked regardless of the ending.
In LLV, Ben’s outer goal was drinking himself to death. Ben and Sera did ultimately achieve an inner peace together before he died, so the tragicness is no different from R&J or T&L in that respect.
redcarol57
April 27, 2012
The problem with unsatisfactory endings is when you spend 2 hours (and at the theater more than 10 bucks and gas to get there), you better like the characters, or end up liking something about them. And if you do find any or all characters sympathetic – you want something emotionally satisfying to a degree for them as well. Two movies that come to mind with unsatisfactory endings were “Smokin Aces”, and “I Melt With You.”
I found myself asking, “Okay? What was the point?” The fact that both movies have tragic and almost pointless endings indicated that 1.) Either the director and/or the writers didn’t have a point, in which case — why did I just watch this? or 2.) The direction and/or writer weren’t making themselves clear.
For instance, the main character of “Gran Torino” wasn’t particularly a likeable character, but the ending had a point and the character some redemption. The writer and director seemed to know what they wanted to say.
JG Sarantinos
April 27, 2012
not seen smokin aces. Loved melt with you. Granted ending was downbeat and weird but congruent to movie. Not all endings must be neat to be satisfying