It is a matter of skills which people find useful. Learning to fly a plane is much harder than learning to drive a car, and almost no-one learns how to fly a p

It is a matter of skills which people find useful. Learning to fly a plane is much harder than learning to drive a car, and almost no-one learns how to fly a plane because it just isn't a useful skill for most people. I did spend time learning all about PGP, and I wish I hadn't bothered, as the skill of learning PGP has zero value to me. On the other hand, learning to drive a car, which took longer, is much more useful.