I think it really depends on the buyer. Some horses are born leery and watchy, but a lot of older horses that have been knocked around and roughed up too many times over the years are made rather wary of people. An abrupt move, a hand waved at their face, a move that looks like you're going after the horse, and they want to get out of there. Occasionally, if a really wary horse is pushed too hard, he might come at you. I haven't seen that happen often, but it does. There was a gal who had a horse like that she really didn't 'get'. She had done a couple really dumb stunts with the horse, and scared herself when he reacted as he obviously would, and she insisted he was a dangerous killer. He wasn't. She just insisted he was and convinced herself of that. The more she got herself convinced of that, the more she jerked on him, yelled at him and jerked her hands at his face - she didn't even realize she was doing any of that. Every time he flinched the tiniest bit or tried to back away from her, she insisted it was 'out of the blue' but he was very clearly reacting to her. That's a mismatch made in Hades. My pony was like that when we got him - he actually was kinda dangerous if you expected him to 'act like any other horse' and tried to handle him like any other horse. I saw someone try that schtick with him, it weren't pretty.