I stopped any sorts of public promotions years ago. Only on-request discounts, like non-profit, educational, or discounts offered personally for some users e.g. beta testers. Prople know there are never discounts so they won’t be waiting and delaying their purchase. Removing the “Discount code” field on order page is the first thing I do in case I integrate a payment processor (why they always have it on by default?)
Giving the product away for 50% of the price on black friday only because it’s a black friday? No way!