Swapping the powerful bishop, which is vital for White's attack.

White does not have sufficient compensation for the pawn.

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Swapping the active enemy bishop in order to seize the long diagonal with the queen.

1...Be5? 2.f4 the bishop leaves the board under worse conditions.

2.Rxf2 Qa5 3.Qe2! f6 4.Qb2 Rf8

Black is just one move from dislodging the knight by ...c7-c6; however...

Insisting on the g4-g5 idea.

White has a decisive attack.

Eliminating Black's most active piece, after which his underdeveloped queenside will become more notable.

With the double threat of 4 Rxd4 and 4 Re4.