Talk:V1.0.0.133/@comment-3430192-20120201185857/@comment-3213322-20120208152610

Interesting reason given for that, actually. In general, mages are required to have high base damages, and so the sustaining effects of spell vamp can readily be taken advantage of with little other stat investment. Lifesteal, on the other hand, requires a heftier investment in AD on the champions that use it, because they start off with relatively low base damage which lifesteal applies to.

(Perhaps a readily visible exception to this rule being Nasus who has a life steal applying ability which does reasonably high early damage in order to make him an asshole to lane against.)