Let's assume you found a running shoe you really like and it works perfect for you, you even got a 20 % discount.
Now you see a different colourway of this shoe online with a 30 % discount.
A few weeks later you find yet another colourway with 40 % discount.
And believe it or not, some time later you can get it for half price ...
How may pairs will you buy?
I was and am in that situation and cannot resist the urge to order online ....