There are often times, particularly when you are training something new or something difficult, when your horse will not do what you want him to do. Sometimes this will be because he doesn’t understand what it is that you want. Sometimes it will be because it is difficult physically for him and he would prefer not to. Sometimes it may be that he is afraid, for example, going into water. Or it may be that he has pain that is made worse by what you want him to do.
It is NEVER that he is trying to make you mad or late or some other reason to do with having an effect on YOU. He is unable to think about what it is like to be a human. He doesn’t have the part of the brain that we use to empathise, to put ourselves in someone else’s shoes, and imagine what it is like for them.
If you reach an impasse in a training task you have asked a few times and got a poor response from him, it is good to reflect for a moment on what the problem might be. Think about simple things first.
Could it be that he is tired and the difficult question could be best asked again tomorrow when he is less tired? Don’t be afraid to stop. Sometimes discretion is the better part of valour. Especially if it is very hot or if he is young. Just go back to something simpler that he will do so that you can finish off on a good note and you can reward him.
Could it be that he doesn’t understand because you are not being clear enough with your aids? Sometimes, for example, I see riders unintentionally pulling on the rein when they are asking with their leg for the horse to go more forward. The rider might be nervous, or perhaps be using their reins to balance. This can be a problem when asking a horse to canter, jump, or go up and down banks, tasks where the rider might be ambivalent and communicate this to the horse, or lack balance.
In the lateral work I sometimes see riders who are asking the horse to move away from the outside leg (for example in travers) but have their weight to the outside away from the movement. If you have piggybacked a child, you will know that to balance the weight you have to step under the weight. It is the same for the horse. In left travers he is travelling to the left so you must sit to the left even as you use your right leg. Check your position, stretch up from the waist up and stretch down from the waist down. Take care that you are being clear with your aids.