Where supporting Ubuntu falls over is when I try and support "power users".

There's like an uncanny valley of competence, between completely naive users who just let things run and experienced users who know where the red lines are when using sudo.

So far I've seen the following breakages:

- completely fuck up apt somehow such that it refuses to update or fix itself

- overwrite packages with their own compiled versions

- mess with the system installed scripting environments

- try and install a new kernel or graphics drivers (usually not even to get something working but because it's "new") and consequently break the boot somehow.