Whether we like it or not, web-world occasionally falls victim to fashion. Some fashions are good, but some are just awful and should be killed off asap.
A few years ago, it was flash intros. Every website just had to have a flash intro banner at the top. It didn't take too long for muscle memory to set in, and soon, "click to close" was a reflex action. You closed it before it even had a chance to open.
Fast forward to today's web. Many websites today include an "exit popup".
You've all seen these - just as you move your cursor away from the page (or even up into the menu area so you can engage with other pages on that site), a popup appears, inviting you to join their mailing list, or to stay in touch, whatever.
Sorry, but I reckon that is just plain rude.
It is akin to someone grabbing you by the shirt-tails just as you are walking out of a store, begging you to come back inside for another look. If something like this happened in a retail store - you'd be filing a complaint for harrassment!
If your website content is compelling enough, people will stay.
If the content is compelling enough, people will stay, or they will return.
Exit popups are distracting, annoying, and they are becoming so frequent now that one simply ignores them.
Today, whenever I encounter one of these popups, I automatically click the "close" button, without even thinking about it.
IMHO the sooner this trend dies out, the better!