Even though bridling a horse is a common part of the riding experience, you may run into horses that balk at the bit, that do not want to let you get a bridle on or that toss their heads in defiance.
One of the biggest reasons a horse may balk at the bit is because they experience discomfort when wearing it.
...if the bit size is fine, your horse may hate being bridled because of dentistry problems.Their teeth may need to be floated by a veterinarian, as sharp, unfiled tooth edges could be causing them pain...
A horse, especially a rescue horse or one who’s entire history is unknown, may simply be associating the bit and bridle with past negative memories.