geezer here - You don't really have to relearn everything every 5 years, but yeah, part of what I love about tech is that I'm always learning and ready to adopt cool new technology when it is truly a better solution to a problem. Experience allows me to see through the hype and know when something new is actually better, something that younger guys lack. I feel really young at heart because I'm always learning. One thing 20-30 year olds should remember, time speeds up as you get older. You will be forty before you know it. Better start creating an industry that can support you when you are older or else you will be the next dinosaur who can't get a job.