"If you stop calculating before the checkmate, you are guessing, not calculating."

The phrase "Igor Smirnov calcula hasta el jaque mate" has become a mantra for students who have installed his methodology. They no longer settle for "winning a pawn." They calculate until the opponent has no legal moves left.

List only forcing moves: checks, captures, threats.
Ignore quiet moves during attack.

Most Spanish-speaking players (hence the hasta el jaque mate keyword) struggle with the same issue: Miedo a calcular (Fear of calculating). They assume that if they can't see the end, they should stop.

When you install the Igor Smirnov philosophy, your brain rewires:

That is the difference. You calculate until the screen says "Black is checkmated."

Set a timer for 15 minutes. Take a sharp middlegame position. Calculate every forcing line until mate or stalemate. No peeking at evaluation bar.