Not going to rate this build, because it is partially good, and partially something I don't like. First off with the build, I see Wriggle's being a malefic item to any hero that isn't jungling. Olaf needs the Merc. Treads because he is often targeted first. The CC reduction is always nice on Olaf. Second, Frozen Mallet benefits Olaf much more at the beginning of the game, and I recommend that before the Youmuu's because of the added health which helps his W. Other than that, the build is pretty good, and I'm a grammar Nazi, so main thing I noticed was "iteam" (Correct "Item"). Not bad though, lot of potential.