I hate them, I hate them so much. I intend to start using some application and suddenly a popup appears "Did you know that x thing does y thing" or "Here you will find x thing" or "New x thing, click ok to opt in". I don't give a damn, I just want to use the thing. I'm usually on edge and I actually intend to do an action, I do NOT want to be interrupted, I won't read your popup, I'll just close it instantly and feel anger.

This is not only annoying, it's dangerous. How do you know a person is not on a emergency and they need to complete an action ASAP?