Pop In Generator

Let me ask you the most important question about Pop Up windows, ok? We all know that pop up windows are effective in increasing opt-in email list(s), conversions and sales, right? If that's the case, why do we have a zillion pop up blockers and why are pop up windows hated so much? I'm asking this question because if we can know exactly why and we do something about it, we'd sure have a new powerful internet marketing tool that is more