My soon to be 5-year-old mare is going through a phase, and it's making me really look at what is actually going on. I certainly am no exception to the wanting to be the best, or train the best horse - no one is the exception here. Every horse has their day, where rider/owner/trainer can ask "why the hell did I get/purchase/take on/etc. this horse?" and recently, this question has been muttered from me too. However, in retrospect, that little 6month old filly that I took on 4 years ago, that couldn't be caught in the stall, couldn't be groomed, much less anything else without trying to bite, kick or run you over then resorting to throwing herself on the ground has come pretty damn far. So, when you're nit-picking on pace to a fence, quality of a lead change, etc., and getting really hung up on it THINK about how many accomplishments you HAVE achieved. Going back to the basics is always OK - can't do a change, well try it simple - can't do it simple, well just stick to plain old straight lines and 20m circles.
When you are training a horse you have to teach the horse, and while teaching BUILD the confidence and not break it. The more hung up you get on the little things can take a toll on the fragile minds of the young'ns (granted, I work with TBs, they don't have to be young to be fragile minded!) If you ever encounter something that is just seeming to blow your horses mind, take it down a notch and reinforce the steps that lead up to what you're asking - give them the courage that they CAN do it.
Obviously, this stuff isn't rocket science, but we are all human, we all tend to forget sometimes....and a little reminder can never hurt!