How Do I Approach These Scenarios 1 Have You Ever Received Bad Customer Service

How do I approach these scenarios: 1)have you ever received bad customer service at a restaurant. How did the employees treat you when entering the restaurant? When ordering? While eating? 2). How far should customer service be extended? hmmmmmm……….. And 3). As the owner of that restaurant/business, what changes can be made to the restaurant? Why?