Have you ever wondered how frustrating it would be if you had to log in each time you wanted to view your Facebook profile? Or in a multiple-choice question where you’d like to mark many options but can’t? Or do you have to enter your card information each time you make a payment since you can’t save it?
These are only a few of the numerous instances on web pages where quick functionality might be useful. Stay logged in for a while, save card details, and much more with a simple click. Basically, it’s a technique to turn things on and off while allowing for multi-selection.