Recently I've discovered a peculiar phenomenon, and I'm wondering if anyone else, particularly in the e-commerce space, has noticed this?
Over the past few years, for a two to three month period around late April to early July, the overall rankings for the site will go down. Many individual keywords might stay right where they are, but collectively, rankings will go down. As expected in this situation, there are fewer visits.
I used to think this was due to a penalty of some sort, because it happened right around when a new Google update (usually Panda) was released. Now I think differently, as it turns out the entire site sees fewer visits (and sales) during this period, so it appears to be less a penalty and more a sales trend thing. People just aren't going to this niche's sites as much during the period.
That got me to thinking: Could fewer visits to the site lead to lower rankings? If Google notices that a site is getting fewer visits, the triggers something in the algorithm to lower rankings as a whole? And if the site gets more visits later on, it'll be triggered to increase rankings.
I've always waved aside speculation that Google is using site statistics to determine rankings, especially because G themselves say this isn't the case, but now I'm not so sure. What does everyone here think?