Hi, i’m trying to do some puzzle but sometimes i just doesn’t understand why my moves are judged bad.
Excuse by advance my expression, i’m french and try to speak english as well as i can…
ok, black has to fight a ko… so i pushed in T19 to capture, and i imagine white will secure and “push back” by the time i capture the stones in “L” : here is the result :
Here is the solution of the problem, why is this position better than the one i propose ? Or perhaps i missed something in the ko fight that i didn’t understand ?
I think it is implicit in the puzzle that the situation is local and white might have ko threats elsewhere on the board. Therefor after you take with T19, white might play a ko threat elsewhere on the board and then after you answer it, White retakes at T18.
in your variation there is a ko black needs to win in order to capture. you assumed white would protect and give up the ko. in an actual game white would look for a ko threat and actually fight the ko. there is no doubt, that this i a very good ko for white. black is the only one who stands to lose something, white can only win. https://senseis.xmp.net/?HanamiKo
therefore it is better for black to avoid the ko and capture outright.
Even if there isn’t any “ko threats” elsewhere on the board, the Ko result decreases the value you gained, because you need extra moves to clean the Ko situation.
So, that why in general, if a “clean kill” result can be reached, it’s always better than a Ko result, especially for a puzzle.