What does this mean?
A slow website speed hurts your rankings and users' experience.
Google has indicated site speed (and as a result, page speed) is one of the signals used by its algorithm to rank pages. And research has shown that Google might be specifically measuring time to first byte as when it considers page speed.
In addition, a slow page speed means that search engines can crawl fewer pages using their allocated crawl budget, and this could negatively affect your indexation. Page speed is also important to user experience. Pages with a longer load time tend to have harder bounce rates and lower average time on page. Longer load times have also been shown to negatively affect conversions.
What to do?
Work on improving your website speed in general
Learn more: https://moz.com/learn/seo/page-speed