If you run a successful business, you should in turn have some repeat customers you can trust. If you do any kind of work and get a repeat customer, do you tend to give that customer any deals? Like deals on products or the work you do for them?
Customers are always influenced by discount which is why it is very important for you to do this kind of a thing every now and then will your business because it is always going to improve the possibilities of making more sales and repeating your customers.