What happens: The horse takes two good steps—he pivots on his hind foot and crosses his front legs over—and then the maneuver just falls apart. His energy drops, and, before you know it, rather than him pivoting and moving his front end away from you, his body is spinning like a coke bottle.
What went wrong: The likely culprit of this scenario is that you got greedy and asked the horse to take more steps than what he was ready for.
How to fix it: Take a step—or two!—back. The secret to great horsemanship is establishing a good starting point. If you find a small enough place to start, you can teach a horse just about anything. When teaching Yield the Forequarters, ask the horse for one correct step and then reward him. Practice asking him for just one step until every time you cue him to yield his forequarters, he gets it right. Then, ask him to take two steps. When he can take two steps correctly every time you ask, then ask for three steps. But if you can’t get one step, you won’t be able to get two. Establish a starting point and build from there. I can’t stress that enough.
When you teach the exercise, look for one good step and then reward the horse. Do not ask the horse to take two steps if he cannot take one step correctly.