Here is something that I am surprised nobody has considered yet...

A few months after I soloed I purchased a new airplane and was very nervous about taking it up, so I asked some instructors if they could look at it. The instructors asked me some questions about the setup and told me that I had been soloed and that I knew enough about the models to safely fly. They would not look over it any further (they weren't being rude or mean). I thought this was bizarre, but never gave it another thought. A few months later after I had flown the plane many times I figured out what a favor they had actually done me. I was like a bird that had been kicked out of the nest. They forced me to be completely self sufficient despite my worries after they knew I could handle it. This had made me a more competent pilot, more sure of myself, and made maiden flights much less of a worry. I had gained so much because they did so little after they knew I was ready.

That was the most important lesson they ever taught me.