Is Google Analytics Worth it?
I keep stats though several different methods. Each page and post records its total pageviews, my server keeps its logs, and I use Google Analytics as a backup. Now according to Google Analytics the most popular page on my site has had 13,000 views over a specific time period; however, the page view the page keeps itself recorded over 20,500 in this same time period and the server logs seem to agree.
Now I know that some people disable Javascript (more use ad-blockers to block the logging script), and there are search engine bots that aren’t filtered out of the raw views, but these differences are huge. Both of these numbers are raw page views (excluding myself), so it isn’t a matter of uniqueness calculations. When I first started to write this aside a few weeks ago the numbers were 12,000 vs. 19,000, so as a rough estimate it seems the Google Analytics misses about a third of users.
So while Analytics gives an excellent sample of your data it shouldn’t be relied upon as your main stat source–especially if it is related to ads.