Why don't people resign?

to #10, this game is my favorite example:
http://en.lichess.org/UJjvZrgH/black

I would always rather play the game to the end, even if it is hopeless. Agreed, timing out is always a disappointment. But sometimes folks get upset with me for playing out a sure-loss to the very end. I do this mainly because sometimes the stalemate presents itself.

To #12, you should try hyperbullet. That's 30 seconds for each side for entire game. No increment. For now, we had a slow 2+0 bullet. I believe you got the idea what bullet games feel like. Thank you for playing with me!
http://en.lichess.org/noZsPKf0/black

Knowing the right time to resign is an art itself. It is a high level of self recognition and respect for yourself and for your opponent. It is a gesture of humility which actually helps to improve your chess. But not resigning and winning is pretty good too.

to #14: I agree for classical. It is pure waste of lots of time to keep playing a lost position. I disagree for blitz and bullet since time is a decisive factor. In fact GM Hikaru Nakamura NEVER resigns in bullet games!
Here is the proof:
www.chess.com/article/view/7-bullet-chess-tips-by-hikaru

Sometimes, not resigning makes you a more resourceful player and improves your defensive ability. I just played this game where I thought of resigning after black's Ne4, but just kept playing as a reminder never to get into that situation again.

http://en.lichess.org/WFDjJBtB/white#65

However, in OTB games that go on for hours, it might not be time well spent playing on in a completely lost position. Whereas, it might be worth playing on in online games, especially considering the time constraint (even for classical games on lichess)

What is silly is when people resign after losing a piece. What about counterplay? I win quite a lot from such a position.