well correct me if i'm wrong, but wands don't have stats on them and staves do. so using wands at a begining of a game is better, because you have too few spells and long cooldowns, and pew-pew is a way to go. as for staff i would use them at mid-late game, cause of +intellect and other stats on them, and you basically don't have time for pew-pew anymore = alot of spells and low cooldowns
