20% OFF
That is what the sales ad promised. Twenty percent off. Meaning that you would save 20% over the normal cost. So on a $100 item that would amount to a $20 savings. Sounds like a good deal but how do you know that the item is worth $100? Maybe it is a $60 item marked up to $100, being sold for $80 and your expected $20 savings is actually a $20 loss!
Maybe it is last years model or worse. It could be seconds. Seconds are flawed mechandise that does not pass quality requirements yet is not completely worthless so it is offered at half price or less.
This is why it is wise to shop around. See what other stores are charging for the same or similar items of equal quality.
I have always rejected most of the sales hype that we are deluged with. You can go broke at a 20% off sale saving money. If I don’t go at all I save 80%.