Reliable, nothing to worry about, you can still get paid if you don't pay. We have it in the gym. In fact, it is a method of recruiting coaches in disguise. Nowadays, good coaches can't stay in ordinary gymnasiums, which are divided into full-time coaches and itinerant coaches, so some apprentices are invited to learn the job at hand while doing it. Have you ever seen a barber shop looking for a barber? Many of them started as assistants, but most of them washed their hair first and learned slowly.