lol, there is a little trick to it if you watch where others go you may learn where not to go. You never want to be that person up front finding the so called land mines (for lack of a better descripton) She does occationally switch them as I was in once and she was picking them up then a friend said the same happened when he was in. My thought on this are when it reaches a point where people obviously know where to go they move them.