I do see that there are so many horses out there bc of senseless breeding. But many are from unworthy studs or mares. These two have proven their great mares. I've won a lot of money off them and saddles. I have yet to go to a show and not have someone compliment my 12 yr old and I've had many offers to buy on both of them. So its not just me. I've had two kids and both times they werent ridden for some time since my body wouldnt let me ride. And the next year I got on them, barely having time to condition them but we won a saddle with in 4 months of getting back to riding.
But I do see the advantage of buying a foal on the ground. I've done this twice. One yearling got a shoulder injury and I did all I could, even taking her to the university vet clinic but I ended up selling her bc she would never be sound to ride. In the pasture she looked fine but once you started riding (as a coming 4yr old) she would begin limping. The next was doing great as a 4 yr old we were sorting calves and cows on the farm and she would freak out. Once even rearing over sideways with me. After that whenever she got pressured up she reared. Once again I did what I could for over a year but ended up selling her for a pleasure horse.
Both breeding and buying are gambles just in different ways.