Hi

First thing I look for is attitude of staff. If Front of House staff is ho-hum with the "whatever" attitude, I say "just looking". And If I peek in and see empty-handed staff just walk by things on floor ... clearing glassware via the "spider fingers" technique (grabbing the lipsticked rims - ewww, as opposed to middle or base), no way I stay.
I figure, although the food may be good, how are they going to handle it -- not to mention the dinner rolls they put in my basket -- when they're handling glassware like this? It suggests "laid back" management's standards aren't too high, or they don't know to teach such things.
Oh, If thers'a a sign out front promoting "Special's ... Pizza's ... Home made Soup's"..., I keep walking. The apostrophe for plurals epidemic can be telling as well. Not very conscientious (and they're going to be handling your food?