2. Pop-up must not be insulting.
Imagine you enter a shop, and a salesperson comes to you and starts trying to convince you that you need a certain product. Is that annoying?
You try to kindly explain him you’re not interested. He insists. You explain again that you’re not into that type of product. You enter a 3-minute discussion why you’re not interested. So to cap it all, he closes his conversation with you saying you’re a complete idiot because you didn’t take advantage of the promotion he’s offering.
Why would you insult the visitors to your site if they don’t take advantage of your offer? You have probably seen Yes/No pop-ups as the one that’s below.
Yes/No popups convert really well. But please don’t insult your visitor. Be careful with what you place in the "reject button" if you don't want your visitors to completly reject you.
I've been looking at Boxzilla for a pop-up requesting email list info. This confirms my suspicion that they work IF used well. You make good points about timing, and it's also easy for us to forget the UX.
I tend to think using Google Analytics to determine avg time on site might be a good place to know when to put pop-ups in. Is this your experience?
I am ok with the pop up that shows up after a long time and or when I am going to exit anyway, it does not matter that that point.
Thanks