I think I approve of this blog posting from a grumpy fella I follow:
Inept or just slow service is saving me a fortune in tips. That, you see, is how tipping works in my world. You don’t get 10-20% just for existing. If I am at your table, you get a tip for providing actual service. That means being attentive, accurate and timely. If you fail in any of these areas without some sort of apology or explanation, you’re going to be taking home your minimum wage remuneration and nothing from me.
things change 
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