I can't see any reason why a search engine would say: "Let's make a rule that under certain circumstances a site won't get any higher than a certain position." But I can understand that people are seeing this behaviour, especially in Google, though Yahoo may have its own version too.

The historical data algorithms can cause a site to jump up or down in the SERPs. Mostly that is visible when a site drops like a stone or shows up from nowhere. But what you can also expect is a site to get stuck at a certain position (and this is all per keyword), simply because the sites above it have better relevance based on its historical data.

When a site doesn't have the required historical data, you can do what ever you want and it won't go up until the historical data allows it. (I know there might be exceptions.)

The interesting thing I get from this thread is that it appears in levels, rather than just the "in or out" kind of behaviour. I kind of knew this already, so this is just confirming it.

But, there's no such thing as a -5 or -10, etc. type of filter. It's like the sand box. Google doesn't have a waiting period for sites to get in the SERPs. It's just a certain behaviour you observe but that doesn't mean it was the objective. You know. you observe the sun going around the earth every day. But does it really do that?

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