What you said can only be true if the redirection is processed by an actual web server which runs JavaScript. The attacks take place using bots which do not follow redirections and do not run JavaScript. Therefore they are completely invisible to Google Analytics.
So the redirection vs 404 is only relevant for two kinds of requests:
- Legitimate administrators who either forgot the (correct) secret word or whose session timed out. If they saw a 404 they'd be confused as to what the heck happened to their site. The redirection to the home page is a clear indication that the site works, the administrator folder has not, in fact, been removed and they just need to provide the correct secret word to log (back) into the site's administrator.
- Nosy people who are curious about your site. Yeah, well, these less than ten people a month will count as a homepage visit.
TL;DR. The thousands of attacks are NOT recorded at all by Google Analytics. The redirection is more user-friendly than 404 to you and other administrators of the site.
Nicholas K. Dionysopoulos
Lead Developer and Director
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