I'm the type of shopper that I can't stand to pay full sticker/sucker price, so nearly everything I buy has been marked down at least once. But my former spouse once said something that really struck home:

"We can't afford for you to save us any more money."

So now I buy something only if I really really need it and/or it's such an unforgettable item that I'd buy it even if it wasn't on sale.

"Would I pay full price for this?"

If I answer no, then I don't buy it.