One morning you wake up and turn on your computer to read your emails. Just like you do every morning. And what do you see? One of the emails is saying: “Hey John! We are low on product “x”, we have only 5 products left in stock. Do you want to refill the stock? How many should we buy? Click here to give the green light.” You click and a web page is displayed where you can say how many products should be bought. You put 10 there and push the “Do it!” button.