This is the third mat purchased in recent years. Hope this one holds up. All others have cracked and do not wear very good. Once they get holes you cannot move a swivel chair around on it.
When I first took the mat out of the box it was sort of folded over to fit the box. I tried putting it under a heavy carpet with weight for a few days with little success. I then put it out in the hot sun for a few hours and it flattened out.