Sicilian Defense: Najdorf VariationBETA

a3 is a slow move that does not develop a piece, control the center, or get the king to safety. In fact, if white castles queenside, this pawn can later become a hook for black to latch onto with an eventual b4 pawn break, tearing open white's king.

The Najdorf Sicilian is one of the most popular variations in all of chess. It is highly theoretical, and leads to extremely double-edge positions with winning chances for both sides. White's lead in development means they can often build up a huge kingside attack, while black has lots of counter-attacking chances on the queenside due to their solid center and flexible pawn structure.