Jakob Nielsen summarised research from Microsoft that confirms that visitors make an almost instant stay/go decision when they land on your website – in fact you have less than 10 seconds to persuade a visitor to stay.

This is because people know that a lot of sites are rubbish, and they are performing a kind of triage where they quickly decide whether your site is worth their precious time and attention.

But if they don’t leave immediately, there is still a high chance that they will leave in the subsequent 10 - 20 seconds.

But if you can interest them long enough to stay for 30 seconds or more, the research showed there is a much higher chance they will stay for several minutes.

So in the first ten seconds:

In the first twenty seconds:

After that:

Take a look at your site and take the 10 and 20 second test.