Developing is not an easy process. Remember back to when you were a teenager. Adapting to your ever changing attitudes and growing body was difficult at times. Some of our bodies grow quicker than we can get used to them. I was clumsy and quite uncoordinated.
Development is a process that never ends.
This is caused by a raise in our level of confidence. We have proven to ourselves that we have the ability to overcome obstacles. That's the clean end of the stick, now let's look at the flip side. Back in 1985 I hit the worst slump I had ever experienced. I was missing easy shots, I was reacting to missed shots in outbursts of anger, and I was not enjoying the game of pool at all.