Winning game auto drawn for no apparent reason?

I just played this game:



Towards the end when it's Q+K vs k, I make a suboptimal move (Qc3+), but I still have mate in 3, I still have 44 seconds on the clock, yet when I play my move, the game just ends in a draw, even though the opponent has two legal moves. Is this some rule I'm unaware of? I can see it says "lost forcing checkmate sequence", but I don't know why that makes the game a draw, I still have an easy mate. (it was also nowhere near 50 moves without a capture or pawn move). I assume it's something I don't know happens, so it'd be nice to know in the future so I don't do it again to my extreme frustration. Ty in advance

Yes I dont see any reason.

@mambodudas its a rule in chess called threefold-repetition (or repetition in short) basically if the same position in the game repeats 3 times in any part of the (same) game, the game will be a draw.

oh my God lol I didn't realize I made a threefold repetition. I'm an even bigger clown than I thought initially. Thanks for the quick response.

Oh ya, didnt see the last 3 moves..

I wonder why it doesn't display "threefold repetition". Would clear things up nicely and doesn't appear specially hard to code.

It is (or rather was) harder to code than you think (as is often the case ...) since the db mostly doesn't store the reason for a draw. But this will actually start being displayed after the next restart.

for reasons like this, I always decide early at which border I want to push the lone king (and this wasn't even severe time trouble)

#4 I was like how can a 1800+ classical rating not know about repetition lol (apparently u didn’t realise it was)

@benwerner - what you write is nonsense. If the algorithm can decide if the game is finished, it can clearly also display the reason.