Fiverr algorithm suggests you by checking others' gigs performance, price and description and try to match your gig if it's failing to show up more frequent in search results. Imagine a situation, where my gig is reaching better, in the category of Web Development and you also have a Web Development gig but reach is much lower, you are not ranking good enough. So, the algorithm checks the critical issues, maybe all of the gigs starting from $40 making better reach than your $5 gig, so the system suggests you to change the pricing to $40 so 'maybe' you can rank better.
I used maybe in quotation marks because the algorithm is just a robot and it is suggest improvement tips based on it's calculation not analytical skill.
Regards.