A lot of the reasons behind it is the community. I consider the community to be the energy of a distribution. Just like in Physics, energy cannot be created or destroyed, just transformed. This is what you are seeing. When Mandriva/Mandrake went under, it was because the community shifted focus to another distribution of GNU/Linux. Most of these changes are caused by the development team pulling an Apple: "Dictate and shape development around what the development team thinks the users need and not what they want.
" It was apparent after they sacked Gael Duvall from the Mandriva team.
Another reason is the hype usage grew too fast and not enough developers. We see that in alot of startup distro's that burn out quick because they spend 25 hours a day working and 0 hours with their friends and family.
Mark Shuttleworth will be the end of Ubuntu. He comes off so pompous and with Mir vs. Wayland, Unity vs. Gnome, the developers have alienated a lot of the community to go to other distributions. I feel that the Ubuntu phone causing the development team to shift focus from the desktop realm to the "cloud" and mobile realm. A lot of people feel their is need of division between the two view points of computing, while others think to drop most support, and shift focus. It has driven Ubuntu from Wayland, and Gnome support to Unity and Mir, also SystemD vs. Upstart. The biggest decider if Ubuntu stands is if their phone succeeds. And with Mark saying that the MS market share bug report and that it is fixed that Linux has a majority of the market share, just shows that he is out of touch with reality. source.
I wish it was fixed, but as a realist MS still has a majority of the market share and that won't change soon...
The true distros that haven't gone anywhere and are still around are Red Hat/Fedora, Gentoo, Slackware, Debian, Suse/OpenSuse, and the BSDs. Gentoo and Slackware because they are very close to the actual source code of the kernels and it is a very niche focused base. Debian and Fedora because they have the strongest Linux community out of all of them. SUSE, BSD, and Red Hat have huge market shares in enterprise world. Free/Open BSDs, CentOS, OpenSUSE have home office/ amateur server community that is anchoring them. They all have stood the test of time and are still around.
It comes down to, the developer's alienate the community, the community loses people to other newcomer distros with new visions, and growing to fast and burning out.Edited by adramalech707 - 6/8/13 at 4:24pm