Page speed optimization isn’t an end-all but it can surely improve your website’s performance not only in technical terms. The website’s traffic can significantly increase, there will be more pageviews with lower bounce rates and longer dwell times. The user experience will improve, increasing conversions and therefore increasing revenue. All these things are interconnected. If you ignore even the slightest underperformance of one aspect, the effect can be felt on your website’s overall performance. Even a 1-second difference in loading speed can affect the website’s performance either way.