Because it happened to me a few times where the cursor will skip or one time the cursor wont even move or be responsive with my finger. The weird part is that once I exit safari the trackpad seems to work again perfectly.. anyone else? Also not sure if its because I have sweaty hands and my fingers are too wet? But its not something excessively sweaty or nasty just a lil moisture I guess on my finger tips at times. update: Nevermind, found out the culprit istat pro.