I was left feeling quite disappointed by the ending of Hotline: Miami.
I really didn't know what to expect from that game, but the game seemed to be starting to reveal something quite genius as time went on, but the ending seemed to almost ignore this entirely.
I learned afterwords that I had the 'basic' form of the ending, because I didn't get the 'perfect' ending, where you learn more. To be honest, I think shutting off endings leaves things quite hollow. I know it means you get the satisfaction of 'earning' the proper ending, but I only learned of it through research afterwords and was left feeling kind of cruddy with the ending.
It seems only detrimental to the experience of a great number of your players to make it end like that.
In addition to this, after seeing the 'perfect' ending, I felt it ignored the interesting aspects of the story.
It reminded me of Metro 2033, no spoilers, but this also has a 'perfect' or hidden ending, dependent on the player too. I also learned of this by researching after feeling left a bit underwhelmed. It was less so with Metro 2033, but it still felt a bit rubbish.