You hate them, I hate them, so why do they exist? Because they have been proven to work (sorry).
Many visitors will be interested in what you are selling, but perhaps not quite enough to buy. Or perhaps they don’t “get” your landing page.
A popup that appears when they go to leave (move their mouse off the screen) giving a final reminder or convincer (perhaps an offer?) to help them decide.
Never use traditional pop-ups!
The operating system based popups that used to be used, are hated by search engines and bad user experience.
Make your popup part of your site and please (please) make it worth reading and great value to the visitor.
If they still leave, well, the argument is “what have you got to lose?” If they are leaving anyway, does it matter if they are a little peeved by your popup?
So think about whether a popup is good for you.
Are they clicking play on your video? Perhaps a reminder would help.
Studies have shown that despite what we all think, pop-ups do convert a percentage of those that see them.
Make up your own mind.
But consider them.