Over the years (Here we go ) I've employed a few old hands and taught a few lads from scratch. It depends on how you teach them AND if they pick it up quickly. They need to be interested for a start, and they must have a motivating point to make them work as well as you. You have a biz to run and it's life and death to you. They are employed, why should they knock themselves out?
Some work flat out all day, some don't. Everyone's different.