Your marketing message should be beneficial to the potential customer. One of these possible benefits is discounts, sales or bonuses.
If you have a lot of products in your product line, you can use daily discounts for different items to attract a potential customer to your store. Today you have one product at a discount, and tomorrow another.
If you do not have a wide range of products, then discounts should be done no more than a few times a year. This can make good money, provided that your customers a couple of times a year will go to your store and spend a lot of money. PR such discounts should start in advance.
Also in your messages to your potential customers, you can use special offers. Example: buy 2 items and get the third one as a gift. Or: buy today and get a discount tomorrow for a new purchase. There are many working models with discounts. And they should be used wisely.
Due to the low price is not always possible to overtake competitors and earn more.