How do comments and complaints help to improve quality of service?

Comments and complaints can be helpful because it allows workers and/or employees to improve themselves by trying to fix a common problem their customers may have.

Example: If you own a restuarant your customers may not like the quality of your food, so you could buy better quality ingredientsto cook with. Or if you own a business you could have a problem with speed and getting things to your customer quickly, you could hire another person to help your other employees.