If a move looks unpromising (late in move ordering), Stockfish reduces the search depth for it.

allot more bandwidth for more promising lines

✔ Meaning

“Bad-looking moves don’t deserve full attention.”

✔ How engine decides a move is late

Moves are sorted by:

  1. Best moves from previous iteration
  2. Captures
  3. Killer moves
  4. Quiet/boring moves

Moves at the bottom of this list are “late”.

✔ What Stockfish does

Instead of searching, say, depth 20 →
It may search depth 12 for a bad move.

If something surprising happens (like a hidden tactic), it re-searches that move fully.

✔ Benefit

Saves time and focuses on promising moves.

Referenced in:

All notes