Just for a moment try to put every shopping trip you've ever made out of your head. Imagine a different world. Imagine that all the goods for sale are locked away in cabinets and to handle them, or even to examine them closely, you need to ask a shop assistant to open it up for you. Imagine that within seconds of entering a store a floorwalker approaches you and asks if you're planning to buy something - then, when you say "I'm just looking," rudely tells you to leave. Imagine any attempt to return faulty or unsuitable goods being met with ridicule, obstruction or a flat refusal to help you.
Until the late 19th century people didn't have to imagine that; it was reality. For anyone alive today a visit to the average store back then would convince you that they didn't really want to sell you anything. The idea of customer service was an alien one. Stores sold things. If you wanted to buy them, fine. If you didn't they weren't really interested. Browsing was strongly discouraged and impulse buys were almost unheard of. Shopping was something you did when you had to. It certainly wasn't something anyone enjoyed.
Then, in the late 1880s, one man came along and changed all that. His name was Harry Gordon Selfridge and this is the story of his life.