A low First Input Delay (FID) ensures that the page is usable. It quantifies the experience users feel when trying to interact with unresponsive pages, which make up for a large percentage of web traffic. Imagine that you are trying to use a website on your phone. It is taking too long for the site to load, and every time you try clicking something it doesn't work because the page isn't responding quickly enough. This experience with this type of unresponsive web page can feel frustrating as well as make users abandon their efforts altogether out of frustration. That's why First Input Delay (FID) in SEO plays an important role: by measuring how responsive web pages have been over time, FID helps ensure that websites aren’t just usable but also enjoyable for all visitors! First input delay is one way we measure interactivity between user inputs and responses from your website—if there is a high latency or lag time then people might get driven off the website.