→ Ubuntu's Not Invented Here syndrome
A well-articulated analysis, the following quote particularly resonated with me:
I don't think that Canonical is bad at what it does. It's just that they're rarely the best and being mediocre (or even second best) isn't good enough when the tournament effect is at work. The winner takes home the pot (e.g., becomes the new standard) and Canonical isn't winning.
Switching to Unity and competing on so many fronts was a mistake, Canonical is spread too thin. Still, the latest LTS release is pretty solid and pleasingly refined. I plan to stick with Ubuntu some more, these days my mantra is to be conservative with platform changes. If things don't work-out, there is always a safe fallback.