Why does a new page’s ranking change over time?

Matt's answer:

Today’s question comes from Sandeep in India. Sandeep asks, when we create a new landing page with quality content, Google ranks that page on the top 30 to 50 results for targeted keywords. Then why does the rank get decreased for the next two or three weeks? If the pages didn’t have the required quality, then why did it get ranked in the first week? That’s a fun question because it opens up how writing a search engine is kind of a complex task. You’re basically trying to make sure that you return the best quality result, but you also have to do that with limited information. For example, in the first minute after an earthquake, you might have different people saying different things. 10 minutes after an earthquake, you have more information. An hour after an earthquake, you have a lot more. With any event that has breaking news, it’s the sort of thing where it can be hard to know– even if multiple people are all saying the same thing, and one person might be the original author, one might be using that RSS. It can be difficult to try to suss out who is– where was this content appearing originally? And over time, over the course of hours or days or weeks, that gets easier. But it can be harder over the course of just minutes or hours. So a lot of the times, whenever you see something ranking for a while, we’re taking our best guess. And then as more information becomes available, we incorporate that. And then eventually, typically, things settle down into a steady state. And then when there’s a steady state, we’re typically able to better guess about how relevant something is. So it is definitely the case that there are some queries that deserve freshness– QDF. There are some queries that are better served by evergreen content that’s been around for a long time. And when there’s a new blog post or when there’s a breaking event or when somebody has just published something on that topic, it can be difficult to assess how relevant something is. So a lot of people think, oh, there should be one– instead of rankings, it should be completely uniform. Everybody in the world should see the exact same thing. And the fact is we have different results for people in different countries, even in different cities. And the results can change over time. Not just because links change or because the content on the page changes, but we basically are able to better assess which pages are more relevant. So it’s not just the case that you write a static algorithm. Your algorithm also has to deal with limited information and then how does it deal when it has better information and better information. So it is expected that, over time, the rankings will fluctuate. They will change as we’re trying to get a better idea based on the information we have about what the most relevant results are.

by Matt Cutts - Google's Head of Search Quality Team

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