Maybe I've just been lucky, but screwed up orders are very rare for me.
Like, for me, a tip is just an annoying exercize in extra math I'm forced to go through at the end of the night. I can probably count on one hand the times I've left no (or a really small) tip due to terrible service. I've NEVER left an extra large one for great service, because I'm not even sure what "great service" is. Just bring me the food I asked for, show up every five minutes or so to fill up the water, and leave us alone, that's all I really want. No way to really go "above and beyond" that imho.
What I especially hate is when the manager comes over just to say hi. I can't even lower the waitress tip in response to this. :(
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to measure the meaning can make you delay
it's time you stopped thinking and wasting the day