Stalemate is not checkmate; therefore it cannot be a win.

Why stalemate should be a win?

The main reason why stalemate is preserved is that it adds strategic flair to the game for both sides. The winning side is left thinking at least in part till the very end to avoid stalemate, and the losing side tries to achieve it, sometimes brilliantly as seen in a few games/puzzles out there.

Is stalemate considered a win?

Stalemate is another type of Draw in the game of Chess. This means that if a Stalemate happens while playing a game, neither side wins or loses and the game ends in a Draw. ... A Stalemate occurs in a game when one of the players isn't in Check, but also cannot make any legal move.