With the waiting move 1. Kh2! White forces Black to abandon some vital defense:
If the Nb3 moves, then 2. b4#.
If 1. … Nb5, then 2. Qa6#.
If the Nd6 moves elsewhere, then 2. Nb7#.
If 1. … Bb5, then 2. Qc7#.
If the black bishop moves elsewhere along the a6-f1 diagonal, then 2. Nxb3#.
If the black bishop moves along the a2-g8 diagonal, then 2. Qa6#.
Note that the white king’s move must be to h2 — any other move leaves him exposed to a check by Black.