The effect of permanent product discounts and order coupons on purchase incidence, purchase quantity, and spending

•Product-specific price discounts influence customers’ total spending following a U-shaped pattern.•Product-specific price discounts influence purchase quantity positively though at a decreasing rate.•Order coupons positively influence total spending and purchase quantity at an increasing rate.•Customers’ expectations of discounts influence purchasing following a U-shaped pattern.•Customers’ expectations of discounts play a moderating role in influencing customers’ total spending.