Because there aren't any alternatives that are as easy to use and understand. QML could be if it was available for any language other than C++. Ditto with Lazar

Because there aren't any alternatives that are as easy to use and understand. QML could be if it was available for any language other than C++. Ditto with Lazarus and Pascal. I hear XAML WPF isn't bad, but it strikes me as having the same limitations Adobe Flex had (performance). People here love to suggest GTK, but I've never used a GTK app that didn't look like a Java swing app straight out of the 90s. Nuklear looks promising if you don't care about "native look and feel". In this age of "web swallowing the world", I don't think I care about native look and feel. Then again, maybe the native look and feel on windows and linux just sucks. All of the gorgeous, yet still fast apps are for the Mac and iOS ecosystems and it isn't because their tooling or native GUI APIs are so much better than everybody else's.