The longer you stay, the more you pay.

NOTE: our reader explained to us that "the planet fitness deal actually does make sense. There are a few different plans. Either you pay something like 56 dollars up front and then ten dollars per month after, or you can buy a longer membership. If someone goes with the 10/month plan, after 18 months they will have paid 56+180=236. So paying 199 up front is actually a better deal if you stay with the gym."