Is Google search site:yoursite.com result count a good indicator of Google's indexing and does it really mean anything in SEO terms?

Question

I'm not sure this is the best stack site for this question. But it does have to do with Google search functionality so I think it is justifiable to ask here. If I'm wrong, please let me know.

My boss likes to check site:yoursite.com almost daily and see the number of results.

He thinks it is good when there is a higher number.

The weirdest thing is that the number fluctuates wildly. One day it will be 37,000, and the next day it will be 300,000.

I've even tried it from two different locations at the same exact time and gotten the same discrepancy.

Why would the same site: search return different numbers of results from two different locations or two different times when the site has changed very little if at all?

Is the site: result count really a good indicator of how well-indexed your site is by Google?

When it's high, does it indicate that you're doing a good job of SEO?

I know that that last question is rather silly, but any kind of answer connecting site: to SEO would help. I don't think the number matters much but I need evidence to convince my boss he's barking up the wrong tree.

Answer 1

Google indexing stores data in eventually consistent manner, so that different frontend servers may see different results coming from the databases, as the indexes are updated. I believe the database structure makes counting the amount of results a very expensive operation, so the displayed amount is just a rough estimate.

Google itself says at http://support.google.com/webmasters/bin/answer.py?hl=en&answer=70920 the following:

"Google's calculation of the total number of search results is an estimate. We understand that a ballpark figure is valuable, and by providing an estimate rather than an exact account, we can return quality search results faster.

In addition, when you click on the next page of search results, the total number of search results can change. Google's search index is constantly changing, and your second search results page may come from a slightly different version of the index than the first page."

Answer 2

I guess technically, you could use this to determine how well your site being indexed, though I believe Google already offers services like this in their Webmaster tools.

When using the site: parameter, you will get all the indexed results associated with your site. I have no idea why you experienced different search results on different days as that has to do more with Google Search's algorithm.