You are right horses, mules and dogs are not born bad. Most are the product of their training. Not evey horse will make a good cowhorse but with proper training should be gentle and rideable. Genetics plays a large part in weather a horse will be an athelete or not. For a mule to be one will have to come from his mothers side, cause his dad was built to pack , pull or Barbeque. Burro ain't bad in a taco .
I don't know that I agree with that, some are a_holes from the start. I have spent a good portion of my life working cattle and showing cutters, and 'bad' is not always a product of training, environment etc. Some are just head shy, bit fighting, contrary POS. That is how the old saying started about a good horse not eating any more feed than a knucklehead. There are millions of genetic knotheads in the horse world. If you get one that never wants to give its head, sticks its nose out when you give it a touch, time to sell, or even give it away.
