Why do people rely on one download mirror?

I'm back with another issue:

I was just trying to download a program that someone recommended for me to try and so I clicked the link to go the the website to read more about it. After reading about it, I click the download link and it brings me to the download site with all of the links to the different versions (Windows, Mac, Linux, and Linux). I click the windows link and it brings me to SourceForge... or did it. It brought up a blank white page so I figured it just wasn't done loading, so I waited... and waited... and waited. Until finally I gave up and thought... "huh... it must be a broken link." So then I say "Wait a minute, let's just search SourceForge to see if there is a different download link..... so I navigate to http://www.sourceforge.net. And guess what.... a blank white page!

This brings me to my final point: When people rely on just one download mirror (SourceForge in this case) and that mirror goes down, they could lose thousands of customers. HOWEVER, if they would've had a second mirror, maybe a small server (nothing as big as SourceForge), I (and whoever else wanted to download this program) would've been able to download it!

Why can't people just use common sense and predict that eventually their ONE server is going to go down? WHY?

-Brady

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