As a trainer, I get problem barrel horses. Without getting in too much detail, I find there are usually two basic issues, 1. The horse is sour (See Performance Horses on this subject), or, 2. The rider has allowed the horse to make all the decisions and the rider basically has lost fundamental control. When I get a problem barrel horse, the first thing I usually have to do is get the horse’s focus back on me and not just on the pattern. This way, I decide when and where I want to enter the course, I can make adjustments as needed etc. without the horse balking when I give my cues.