all true but some people just have a thing about wasting money, like me. i've worked hard and been blessed financially, just bothers me to buy another tool just because it's a good price. If i upgrade for some reason, i tend to get rid of the older tool.......move it to someone else for a good price.
I only upgrade tools if there's a benefit -- more features, longer battery life, more power, etc.. Then as far as the old stuff, I usually keep a spare/backup of a tool. The 3rd string tool usually gets given away or sold for cheap.
I enjoy giving away tools to those less fortunate. I hired a guy to pour some walkways at my mom's new house. He did a great job and didn't charge much. I noticed his tools were kinda lacking. He had an old Craftsman Ni-CAD cordless regular drill (taped together). I was joking and said "that poor drill's seen better days", and then he related that he had been sick a few years with a heart problem and couldn't work. He was just now getting back working again.
I gave him a fairly new Ryobi One+ lithium set -- impact driver, regular drill, reciprocating saw, light, 2 batteries, charger -- all in a new neon green Ryobi bag. His eyes lit up and he thanked me about 10 times. He and his wife are now good friends with my mom, and if I am too busy to go and help her with something, he usually does. Doesn't charge much. She has to sometimes force him to take even a $20.