You should never knowingly sell someone a broken product
Bob is working at an electronics store when he realizes one of the computers is broken.
Bob wants to sell the computer.
Bob offers the computer to a customer as is at a massive discount.
Bob puts the computer in a box and sells it to a customer.
The customer is happy that he is able to get the computer for so cheap.
The customer is not happy when he finds out that the computer doesn't work.