The difference is that you don't get a 2nd, 3rd, 4th, etc rated selection with a system and for those of us that develop ratings and bet on our selections based on the level of value, this is often where the profits come from. Backing just a 100 rater is a quick way to the poor house unless you are an absolute genius, many times my 2nd or 3rd rated horse has won paying more than double my rated price.