Personal Opinion: If someone is going to be in a supervisory position, they first need to know and understand what it is like to be the one who is supervised. Learn from those experiences - what works, what doesn't work, what would they like to see in a supervisor, and what would they not want to see? Then, develop the good, and work to eliminate the bad. You will gain the respect of those you supervise when you can identify with and understand their struggles, not when you are ignorant of what the "little people" experience.
I desire to hold a supervisory position someday, and in the mean time, I take every opportunity to learn from my current experience. Whether it is the lessons I learned from working in a grocery store at the age of 15, working in a gymnastics center and running child birthday parties, working in a restaurant as a hostess and carry-out girl, or working in human resources... everything is a learning experience, and goodness knows I have learned a lot with my (almost) 10 years experience in the workforce. Not all of it has been pretty, but it has certainly been...an experience.
