Amateurs vs Professionals

What do we know about the difference between amateurs and professionals, apart from the money they make?

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Here are 2 examples:

1. Amateurs usually work with their "bare hands"; whereas professionals usually work with tools.
• Question: If you're going to visit a dentist, would you choose a dentist who works with bare hands? Or would you choose one who uses the latest sophisticated dentistry tools?
2. Amateurs go into the arena with no skills, do trial and error, and count on luck to produce good results; whereas professionals practice diligently on a specific set of skills before going into the arena, apply the skills in the arena, expect certain results from their effort, and assess their skills and results after the ordeals are over.
• Question: If you're going for a live football match, would you pay money and spend time to watch a group of amateurs play? Or would you rather pay money and spend time to watch a group of professionals play?

If you want to be good at something, treat it with a sense of professionalism. If you respect what you do, people will learn how to respect what you do, and so you'll get the results that you want.