Do that and you risk visitors leaving, never to return.
So don’t use this annoying method to try to force your visitors to comply. It’s better to make the X button large, so it’s visible and easy to click on a small smartphone screen.
You can also have a "No, thanks" button that they can choose. If you're worried about no conversions, you can use psychological tricks to keep visitors guessing if they click.
For example, if you sell weight loss supplements, you can offer two options: “Yes, sign me up!” or “No, I’m happy with my current weight.”
In many cases, people who visit your site aren't comfortable with their weight - that's why they're there. So this could play on their insecurities, making them more susceptible to signing up.
But be careful about your negative reverse psychology. It can backfire if you come across esinc email list as sleazy or rude.
When you're getting the attention of the people you're trying to convert, you want to make the process as quick and easy as possible. The number one rule for your forms is to keep them short and sweet.
When creating forms, make sure you only ask for information that you really need. If you can get away with just asking for a name and email address, then let it be.