User blog comment:Megames1/Against the Meta September Edition/@comment-1153246-20120923225840

I think it always really depends on the champion. Certain AD champs lend themselves far better to it, such as Tryndamere and Gangplank (who even has a case to make for full AP on occasion), but some don't really have the ratios to justify it, if they have a ratio at all. Obviously Olaf has absolutely no reason to play AP because he doesn't have a single ratio, but someone like Pantheon, with 1:1 ratios on W and R, may look appealing without actually getting very much in the end - building anything but straight AD detracts from their overall damage output.