I once thought, "No one is perfect". Then I remembered I was perfect, but it was too late, I made a blunder. Now I am not perfect anymore. This is kind of sad, and I, of course, am being absurd.
You can severely hurt yourself if you rely on the opinions of others, including bosses who look forward to finding fault rather than to catch you doing something good.
When I, in my former life as a consultant, found a boss that was constantly critical I suggested that the boss not overlook the fact that the boss is the ultimate person responsible for training the employee and setting the tone of the company's professionalism. When you point a finger,there are four fingers pointing back at you.
When customers interface with a positive company, a company where everyone is important and is charged with maintaining the image of the company, the customer feels appreciated. The customer feels there is someone looking out for their back. The customer feels integrity oozing out to help the customer feel safe.
When a mystery shopper reports an incident, the boss should see that as an opportunity to analyze and train if necessary, not beat fear into employees. Rewards come to those who have repeat customers as they do not have to waste time and money finding new customers. Loyal customer's "Word of mouth" referrals will find those new customers for the company, and the company should share the profits with those who create the profits. Everyone wins if the purpose of the company is to create value for the customer and deliver that value pleasanty. Customers will talk about you and say nice things about your company, how much they enjoy working with your company even when negative issues occur if you deliver that value pleasantly.