Golf ball compression is a measurement that defines how much a golf ball deforms during club impact. Many golfers feel that using a higher compression ball will add distance to tee and fairway shots, which is a common misconception. According to the U.S. Golf Association, it is highly unlikely that compression differences will result in better performance.
An article in Gold Digest quoted Mike Sullivan, Spaldings vice president or research and engineering. Compression has a lot to do with feel. If you want a softer feel, go with a softer compression ball. We find that everybody wants a softer feel if they can get it. Some people still use a 100 compression ball because they have it in their heads that without it, they are giving up something.