I also refuse to use IE 10 or 11, unless truly necessary, which is less the case these days. Though I believe that on Windows 8 & 8.1 OS's, something's accessing IE anyway, as when I run CCleaner, there's a lot of IE files to be deleted, though I never opened the browser. This is wasted bandwidth for those on a cap, like those who has a cell based ISP limited to 5GB/month. Should be a way, w/out going into the settings & totally disabling the browser, which will cause a warning to be prompted & why I didn't do it, to prevent IE from self-use. Maybe it's the Mail, or other Tiles, though I have most all of these turned off, or the Bing Desktop, which I use, to get a new wallpaper everyday I decide to use Windows.
My reasons are different than that of Queen-Evie, but still they're valid to me. IE is open to few 3rd party extensions (add-ons). There are now a select few available & these are watered down from that on Firefox/Google Chrome, especially Adblock Plus. The normal configuration screen doesn't show on IE after install, where one has malware blocking, remove social media buttons & disable tracking. Those are three key elements of the extension. I don't know if this link will copy/paste properly, but I'll try.
Web of Trust (WOT) works OK & that's about the only one that does for me. That is not a compelling reason for me to use IE, nor any other browser, just an extension to warn me of possible dangerous Websites. It's not 100% accurate (a few false-positives), though it does a good job of warning of shady sites.
And there's one option in IE, enabling Enhanced Protection Mode, which requires a restart of the computer, that wipes out those extensions, as they're not compatible with EPM.
Most likely, if it weren't for business & education use, IE would be nowhere near as used as reported, as many home users has an alternate browser in Google Chrome, Firefox, Opera & a few lesser known ones. As far as I know, Safari is no longer a Windows option, though this could change. Everyone who uses a computer needs to have an alternate browser installed & know how to use it anyway, as if the server that controls IE goes down, one cannot even grab a 3rd party browser on that install.
There's an IE Tab extension in Firefox to view sites in native IE Mode (for Windows users only), this works for many sites that requires IE, except Windows/MS Update for XP & earlier. That still has to be accessed through IE.
Since the release of IE8 in 2009, which literally crippled my XP SP3 install & Firefox 3.5(RC at the time) came to the rescue, I've not looked back at ditching IE & it's highly unlikely I'll change my mind. Firefox/Google Chrome has more to offer, is faster, has security extensions, can have the configuration I need.
However for security reasons, I highly encourage all IE users to upgrade to the latest version possible. That would be IE11 for Windows 7 SP1 & 8.1 customers & at the current time, IE10 for Windows 8.
XP/Vista customers are stuck with IE8 (XP) & IE9 (Vista), it's best to go to a alternate browser anyway.
It's still understandable to me why dropping support for older IE versions, these costs lots of time & cash to support & their competitors are doing the same. If one wants support for Google & Firefox, these has to be kept updated. So I don't see the stopping support of a 5 year old browser (IE8) & 3 year old in IE9 as an issue. By 01/12/2016, IE8 will be nearly 7 years old. Neither Google nor Mozilla would think of supporting a browser half that long, let alone do it.