Because it's not just the natural results that matter
We get all the positions of a SERPs. The natural results obviously, but also all other types of positions.
We recover the first 100 natural results of each keyword.
We recover every day P0 of your site. Using our evolution charts, you can see for each keyword the loss of P0 in time.
We retrieve the first 4 PAAs from each SERP and detect if your site or your competitors are positioning themselves.
We detect if your site is positioned in the Videos block, usually at the top of the search results.
We recover other types of results. You can track your Google Maps / Google My Business listing, your site in the News block, and detect sites that advertise on Adwords.