Why does my pony struggle with left canter?

Hi! Trouble striking off on one lead or the other can have several causes. The horse is not fully straight and is stiff on one or both sides. An underlying injury can make it harder to canter on a particular rein. The rider is unaware of their own crookedness (far more common than you might think!) and unknowingly puts the horse in a position that makes one lead easier or harder than the other. My best tip is to get help from a knowledgeable trainer who can work out where the cause lies, and to check that the horse is comfortable in its body. 🙂