Believe it or not, some folks are taught to never resign. I don't get it either, but it is their right to play on in some delusional hope of stalemate.
why do some poeple never resiging in online chess?

What does it matter if they resign or not? It's their game as much as yours, so let them play it out if they wish. If they're truly in a hopeless position you've got them beat ether way. So why fret over them not resigning?

resignation is called volunteering to lose...Fight hard to the very end, and maybe your opponent will give something away
I say keep fighting! I have won many a game where my opponent lost on time or made a terrible blunder in an otherwise won game

Chess is played by normal and abnormal people and by normal cats.
Abnormal people play in ways that have no relationship to the omnipresent intelligence of the universe.
I hope that helps.

1) They don't know chess games normally end with resignation (or that it's even an option!)
2) They and their opponents blunder mate in 1s to eachother so they don't see the point.
Guess that's already been covered in this topic though.
Oh, and as they transition away from these there's 3:
3) They're jerks.

I would ask: Why prolong a game for 40 moves because your opponent won't resign? Checkmate them as soon as possible and end the game!

oh, and don't forget this MAJOR FACEPALM! http://www.chess.com/echess/game?id=96718812

AngryBird5217 wins...by time...when his opponent was just one move away from winning...because he got banned.

I would ask: Why prolong a game for 40 moves because your opponent won't resign? Checkmate them as soon as possible and end the game!
that was my whay trying to teach him to resign. bu i didn´t work. his is doing it in another against me. and i am going to try to promote as many powns as possibly to knights and bischops
http://www.chess.com/echess/game?id=95856332
i have played some poeple at online chess who never resiging and won't explain why they keep playing. are you one of those poeple? please explain why you don't resiging when the possition is lost.
here is an example
http://www.chess.com/echess/game?id=95856342