DietersMistakesIn2022/Solution5

Move 97  

Taking control at the centre and top is more important than defending the bottom. If Black tries to kill White, there are enough moves to create eyeshape.

Move 97  

The game move was slack. Black gets out with both groups and White has to take care of floating stones.

Failure to surround and force a big group to escape or live small, in favor of slow defence.