hikaru vs Ykow2

White pushed the b‑pawn from b4 to b5. The move opens the a4–c6 diagonal, so the bishop on a4 now eyes the black knight on c6 (the listed white threat). However the push also abandons the pawn on b4, leaves the d4 pawn and the bishop on e3 undefended, and does nothing to stop Black's immediate threats: ...d5‑xd4, ...Re6‑xe3 and ...Bb6‑xb4. In short, White creates a modest future target while Black retains concrete tactical chances.

The engine’s recommendation, 34.Bh6+! Kxh6 35.Rxe6, exploits the fact that Black’s king is already exposed on g7 and the rook on e6 is overloaded. After the sac, White wins the rook on e6 (and often follows up with Nxd5 or Rxe6) gaining a decisive material edge. By contrast, 34.b5 merely shifts a pawn and leaves Black’s threats untouched, allowing Black to consolidate or even win material. The engine line forces a win immediately, whereas the pawn break is a slow, non‑critical move that does not address the opponent’s active pieces.

Forceful tactics over idle pawn pushes: When the opponent has multiple active threats, look for forcing moves (checks, captures, sacrifices) that exploit overloaded pieces. A pawn break that does not neutralize opponent threats rarely yields an advantage; a well‑timed sacrifice can turn the tide instantly.