Does $0.25 a minute sound good as a pay for labor?

It works out to $15/ per hour. Which is minimum wage in some jurisdictions?

Does it sound better per minute or per hour?
What is one only gets paid for every minute that you actually work and not goofing off? Or should people not have to work at 100% at full tilt, constantly? With only breaks of 15 minutes every 3 hours?

What are some careers that one is required to work at 100%. Like sports and emergency personnel and military?