Because Black plays first, White receives komi — compensation added to White's score; AGA komi in an even game is 7½ points. The AGA raised komi from 5½ in August 2004, effective 2005; the half point prevents draws; In a handicap game White instead receives ½ point, again to ...
Why people argue about this
People often assume that komi is just a random bonus point given to White at the start of every game, forgetting that it's actually compensation for Black's advantage in starting first. This oversight leads to misunderstandings about its purpose and how it affects outcomes.