I worked in car dealerships for several years, often training or mentoring young mechanics, I was also one of the guys who would introduce the new guys- including management and new factory reps- around the shop.
"Anything Shocker can do I can do better and faster." (this was when introducing a friend whom I had worked with for many years. He is a good wrench, but he and I know I am better
"If you are going to be successful working flat rate you have to approach it like having sex in an elevator. You take off as little as you can in order to get the job done well before the doors open." (The kids always like this one because I said "sex". But after they thought about what I meant by it, it usually resonated with them for other reasons).
""Some is good, more is better and too much is just right" is a recipe to fu*k it up!"
"You might not have enough time to do it right, but you damn sure will
have time to do it over."
"If you screw something up, tell me and I'll show you how to fix it. Don't tell me, you are fired and I will have to fix it myself."
"Learn from your mistakes, but remember that the worst mistake to learn from is lying to me."