When viewing the Google Search Console stats for the amount of time Googlebot spends downloading a page, it is common to see wide fluctuations in that time.  But while it is sometimes easy to guess the reasons, sometimes it isn’t always clear.

John Mueller from Google answered a question about the report, specifically why there are changes for a site that hasn’t made any changes, yet the report shows these wild fluctuations.

The fluctuations aren’t necessarily from a site undergoing a lot of changes, needing more crawling.  It is based on the actual pages, and if some pages are bigger, or have more resources that requires Googlebot to process, you can end up with a report that has large swings in the time spent downloading a page.

Of course, the reason can also be specific to the site, such as the site’s server being slower on responding to Googlebot crawl requests on a page as well.

Here is the tweet: