Search engine results page (SERP) volatility occurs when there are some major fluctuations in the search engine rankings over a period of time. Why Is SERP Volatility Important? We must pay attention to the SERP volatility because it can impact our client’s visibility and performance. There are a bunch of different tools to measure SERP volatility, which are listed below. Mozcast is one of my favorite tools to look for SERP volatility.