I voted for all the categories.
I learned/learn from every available opportunity and at 49 yrs of age, I still do to this day. My Dad has been a huge influence on me as he instilled the idea of self reliance to me on a daily basis. A 32 yr Air Force veteran, this guy can fix anything and that's not an exageration at all. Fabrication, mechanical, electrical, woodworking, carpentry, whatever it takes.
My neighbors were/are Tool makers/Machinist. I followed their footsteps on my fathers prodding. I worked in the field for 13 years and had formal school training/apprenticeship as well. Most people do not realize that an apprenticeship in Tool & Die includes Welding, Hydraulics, Pneumaticsd, Drafting, Metallurgy and other Mechanical theory.
My brother-inlaw, was a Bodyman/shop owner and Stock car racer. I learned many of my on the fly skills from being his Crewchief for several yrs. Having to think fast at the track, really improved my ability to analize quickly. I thank him for those years.
The Collision repair is self taught with OJT, not being afraid to ask questions, lots of internet research, reading and just aspiring to produce better work on each repair.
My son is 21 and is one of those people that once you show him something, hes got it. All his friends kid him about what they say when they are confronted with a mechanical issue they are not familiar with. They say WWKD or what would Kevin do ? That's the biggest compliment a person can get.
I think the best thing I can contribute is this post is, Keep learning and spread the knowledge you have obtained. We cannot allow the knowledge of skilled trades and practical experience to wither. Teach what you've learned every chance you get ! The recipients will be greatful for your generosity