This is definitely true in the case of some of my horses. I have had a difficult horse and he turned out amazing. I'm now working with another horse who is even worse and I'm sure he'll have equally as much to offer
I never thought I'd have a horse, but it happened, and boy am I happy I was FORCED to wait! I wouldn't trade my horse for the world. Keep dreaming guys, you've gotta work in order to have this dream. If you work for it, you can get it.