The younger ones, up to about 11-12, LOVE the pool and come over to use it often. But these are the same ones that just love being at the grandparents' house, anyway. As they become teenagers, or even tweeners, they mainly want to use the pool when friends or cousins are available. Older teens then want to use it only on occasion when they haven't swum for a while, or there is something special going on, though they will also often see it as a good way to cool down in the heat of summer.

In our case, the kids have to come over, so it's not the same as having a pool in your own yard. That's my experience, YMMV.