Somehow I don't think that time is the bottleneck here... The problem is that as you become an expert in a new area, you soon cease to be an expert in the old a

Somehow I don't think that time is the bottleneck here... The problem is that as you become an expert in a new area, you soon cease to be an expert in the old area. It's difficult to stay up to date and also to keep your skills fresh. If you don't practice a skill for a long time, it tends to decline.