It depends how one looks at it. Technically Linux is a perfectly fine desktop OS, I'd contend that as far as user friendliness on the desktop goes, Windows or OSX have nothing on desktop distros such as Ubuntu or Fedora. Many organisations have deployed Linux desktops and are happy with them. The general public uses Windows (and the rest OSX) not because they conclude that these are better desktop OSes, but because they come preinstalled. People just regard them as being an integral part of the computer they buy. I know an otherwise perfectly sensible person who had a Windows laptop, used it every day, was happy with it until the day the came to ask me to help her because she would like to buy "a computer that has Paintshop Pro". After some discussion I understood that she never realised she could actually install new windows apps on her laptop. Thus the point is, the general population doesn't use Windows or Linux. They use "a computer" and don't generally care (or even know) what OS and software it runs. Linux's problem in that area is not the OS itself, but compatibility. LibreOffice is nice and well and its MS Office compatibility is usually good, but people send each other photos as MS Word documents with pictures embedded in them through OLE... Until LibreOffice can open such stuff flawlessly every time with 100% reliability, until the most popular game of the day runs on Linux (without having to deal with GL driver conundrums) and until mouse pads sold in your local supermarket are advertised as being "linux compatible", there will be no Linux on the desktop for the wide public. Linus made the OS technically capable of making a great desktop, but this is not something he can change.