My e-commerce–focused website experiences significant and recurring ranking fluctuations. Especially during periods that coincide with Google updates, I see strong ranking boosts across the entire site for high-volume, commercially targeted keywords. During these phases, many keywords reach the top 3 positions, generating around 100–300 clicks.

However, within a few days—or at most 1–2 weeks—rankings decline again, dropping back to page 2 or 3. This pattern repeats regularly in cycles of 1–3 months.

When I analyze the SERPs during the same periods, I do not observe similar dramatic rises and drops for other websites. Competitors either remain stable in their positions or, when they rise, they tend to maintain those higher rankings more permanently.

The overall authority of my site is competitive, even stronger than some competitors. We are also running active advertising campaigns to support traffic acquisition. From a technical SEO standpoint, there are no major issues.

This pattern creates the impression of an algorithmic “testing phase” or a site-level filter. It feels as though Google is testing the site in higher rankings but not allowing it to remain there permanently, instead pushing it up and pulling it back down in recurring cycles.

What could be the possible reasons behind this situation?