WPMU Dev checkup I am getting a red background for URL Structure: keywords

Hi,

On the WPMU Dev checkup I am getting a red background for 'URL Structure: keywords '

It goes on to say:

We could not detect any keywords in your URL. Having the right keywords in your URL ca
n increase your search click-through rate.

Then the question back has this in it:

If you’re trying to optimize a blog post for a certain keyword, you should include that main keyword in its URL. Having the right keywords in the URL structure can increase your search click-through rate.

Can someone explain why this is red, as all the blog posts titles are correct for the blog posts, with SEO urls and the blog posts have the keywords of the title in them.