[Mogzol]

The whole point is to determine if you have full internet access, so you want to make sure that an HTTP request returns the data you're expecting. You may be able to get DNS responses but not have full internet access, like when on a public wifi that redirects all requests to a login page.

[Eleison23]

What is "full" Internet access?

I mean really, what does it mean to you, or to Windows, that I have "full" access to the Internet?

For me personally, I only visit a few walled gardens, so as long as I had my Google, my Wikipedia, and my work-related sites, I wouldn't miss 99.99% of the Internet anyway.

But what if your ISP blocks a whole bunch of ports? What if Adware has taken over 33% of your DNS space? What if you're behind a Great Firewall of <Dictatorship>? What if there's some sort of Balkanization or segmentation of your side of the 'net and you can't reach a lot of stuff? What if Cloudflare's down again?

[Mogzol]

Yes, "full" internet access is a hard to define term and this simple test doesn't cover all possible cases. But it will work in probably 99.99% of cases and honestly I think that's good enough. If it doesn't work you end up with a little "no internet connection" icon in your taskbar and that's about it. You can still use the connection, so I don't think it's a big deal that this test isn't 100% accurate. It's still more useful to the majority of users to have a slightly inaccurate test than to have no test at all.