An "aha" moment I had a few months ago regarded the transition from trot to walk.
When I transitioned from trot to walk I got the walk but it was a ambling walk, not energetic at all. Then I gave him a kick to get the walk I really wanted.
One day I had an "aha" moment that made me realize I was punishing my horse for doing exactly what I asked. Instead of asking for an energetic walk, I was asking for a cessation of the trot.
What's the difference? Lots. Asking for cessation of trot can mean lots of things.... walk with energy, ambling walk, halt, slow trot, quick walk. Asking for an energetic walk means just that..... an energetic walk. Its not your horse's fault if he doesn't answer correctly if you don't give a clear question.
So... if you are transitioning from trot to walk, ask for the walk you want -- not the cessation of the trot. As you are trotting, start to visualize the desired walk and then clearly ask for it.