You imagine that your work should be a smooth flow of operations: confident, swift, and deft. At the least, you feel like you should always be moving toward that adept ideal. In reality, although you are learning and improving, you are also expanding your range of operations and challenges. You are still making mistakes. You are still re-doing things, getting frustrated with yourself. Sometimes even in simple operations you have done many times, you might skip a step or mix up some bolts. You might even break something. Steady on. This, too, is part of it, but it only becomes a deterrent and frustration if you allow it. By focusing on the kind of mechanic you artificially think you “should” be instead of being the imperfect ape you are, you create a conflict between desire and reality and thereby suffer. Steady on.