Surely these posters exaggerate the importance of micro-engineering when dealing with bicycle mechanics. I started auto mechanics with my first car, a 59 Chevy. After 40 years, I would give the same kind of advice to a beginner. You're going to make mistakes, but that is part of the adventure of life. they build wheels in high speed factories just like they build so many other items. I imagine it is what happens to the wheel after that which could cost you $40,000.