A few years ago, a colleague told us of a local petrol station that was offering 10 × 22 compact binoculars for sale at £2.99 each. On the reasoning that “you can’t go wrong at that price,” the colleague acquired a pair for his son, who was very pleased with them. Upon hearing of this, another colleague went to the petrol station and bought a pair for herself. When she got home and tried them out, she found that they gave a double image, obviously a case of poor collimation. She returned them to the petrol station, where the sales assistant took them and, without even checking them, placed them in a box and replaced them with a new pair out of another box. My colleague was satisfied with the replacement pair and pleased with the “service” she received from the petrol station.