There are people who make mistakes, won't admit to them, and don't learn from them. There are those who make mistakes, admit to them, and learn from them. Guess which one improves the most over time? This week's guest contributor, Randy Beikmann, is the latter, not the former. Having spent time with Randy, knowing his background as an engineer and author of the Physics for Gearheads book, it's not surprising that he's able to admit to making a mistake, or that he continues to learn.