Did you know that a well optimized for SEO content will not show a steady growth of visitor traffic at first? When you publish an article or a video that is very well optimized for a specific niche you will see random spikes of visitors that seem to come out of nowhere. From our experience this is “Testing” phase for google. They will shuffle around content ranks from time to time to get fresh content out to the accurately measured public. This test run will measure engagement rate, user retention rate, bounce rate, time spent on a page and so on and so forth. If your content generates good stats it will likely get promoted further by the algorithm and you should see an increase number of popularity spikes which will transform into a steady flow of new visitors. Now, next time you’ll see strange spikes in your website visitor graph, you will have an idea of what they are. Again, this info is guarded heavily by Google and no-one but google knows how the algorithm works. Thus, this is only our interpretation.