There has probably been at least one time when you noticed that one of your pages used to rank for a certain search query, but then later dropped for some unexplained reason. Matt Cutts, in the latest Google Webmaster Help video, talks about why this might be the case.
Cutts responds to the following submitted question:
When we create a new landing page with quality content, Google ranks that page on the top 30-50 for targeted keywords. Then why does the rank get decreased for the next 2 to 3 weeks? If pages didn’t have required quality, then why did it get ranked in the first week?
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