I am in Miami for a few days. My guidebook has this to say:
Miami restaurants are notorious for slow, arrogant service, by the time you finally get your cutting-edge dish of pan-roasted, pan-seared whatever, the trend that created it may well be long over.
I can verify, last night I walked out of two restaurants. A little while later the guidebook also notes:
…many restaurants top up the bill with a 15-18 percent gratuity …
Also true, as in Europe Miami restaurants tack-on the "gratuity" automatically. What the guidebook falls to mention is that the latter fact explains the former.