For starters, because you don't have a crystal ball handy, and because once it gets rolling that tiny difference won't matter if you have accumulated enough and don't dwell on it. I've known I could have made much more over the years with absolute knowledge of future price moves, but ya just have to make a decision at some point and live with it. I realize it matters more if you buy all of your shares at .035 or .04 instead of .025, but again, it's a roll of the dice to wait for a lower entry point without knowing for sure it will happen. Nobody here without inside information would know for sure, so you could easily miss a spike that never pulls back. It's a gamble. If you do get a crystal ball please share in PM's! lol