I never return to a store if I hear the employees discussing and complaining how they can't get time off or 'so and so' did something or they hate the amount of work they have to do and nothing's "fair". And also if they take smoke breaks all huddled together outside where customers can see them. None of this is professional and I see and hear these things OFTEN. But when I see people working and talking amongst each other about work and their care for the company, I go back! What an excellent question!
having great sales associates that really know their stuff. also, if the customer has a problem, ( no matter haw insane and stupid it is) remember "the customer is always right!" having a good attitude and always respecting everyone who you come into contact with at you work place.