This time is made up of the socket connection time, the time taken to send the HTTP request, and the time taken to get the first byte of the page.
Often, a smaller (faster) TTFB size is seen as a benchmark of a well-configured server application.
Since many search engines, including Google, employ a ranking algorithm which is affected by a page’s loading speed, these optimizations can impact a website’s placement in search results
the time taken for the full page to render and be visable and usable. Slow loading pages are abandoned before they are loaded.
Speed Index average!
If your website pages or your server is slow, it will need to be redesigned or optimised as you are loosing ranking.
Lower ranking means less visitors, as peplo are impatient and dont like to wait.