How do I manage customer expectations around discount frequency?

As an e-commerce business owner, I'm struggling with maintaining customer interest in my promotions without training them to always expect discounts. I've noticed that frequent sales are eroding our brand's perceived value, and customers seem to be waiting for markdowns instead of purchasing at full price. I need a strategic approach to manage discount expectations while still driving sales and maintaining customer loyalty. How can I create a balanced promotional strategy that doesn't compromise our brand's pricing integrity?