I would be willing to take a mature sheep dog into a field that’s never seen a sheep and let it off and it would set off and try to round up the sheep. You can take a mature unbroken horse to a race track and you can let it off and see if it goes galloping round the track. That’s when you see the difference between training and breaking.
If a horse doesn't want to race, it doesn't. It's not uncommon for a horse to refuse to race. So it doesn't.
