My horses come to me when I call or walk out into the field, so none of them are hard to catch.
Usually, they're jockeying for position to determine which one of them will be first to get his halter on and led inside for dinner.
If you're going to leave a halter on a horse because he/she is hard to catch, then at least buy the animal a breakaway. It only takes a second for something bad to happen, and nylon halters don't have any give.
If all the horse has is a nylon halter, my rule is that it gets taken off at the gate before the animal is turned out. No exceptions.
If you have a hard time getting a horse to accept a halter when you go out to get them, there are gaps in your training.