I started working on an ASP.Net MVC based CMS on which this site is built in 2008. I lazily maintain it today. I chose to build this rather than use WordPress (or other CMS) because I don't know PHP, nor do I really understand WordPress and I was too lazy to learn. OrchardCMS hadn't been released then and DotNetNuke was all WebForms and not "mordern" enough for me. I know these are excuses for reinveting the wheel, but yes, that helps me sleep better at night.
That I may not be able to disclose yet... *wink*