I've used Linux exclusively for several years now, but problems that killed earlier attempts were:

• I'd encounter a hardware driver issue I didn't know how to fix (Nvidia...)
• I'd dual-boot Windows for playing games and maintaining both OSes was too much (this was pre-Steam client on Linux)
• I wanted to customize some setting that the desktop environment's control panel didn't support, and I'd have to copy/paste terminal commands I didn't understand, usually breaking something which necessitated a reinstall.
• Ubuntu would provide outdated / buggy versions of software, and installing the newer version meant installing PPAs which could conflict with other packages / cause other instabilities I didn't know how to fix.

The first two have seen massive improvements but I still find most desktop environments limiting if you aren't a terminal expert / Arch type of user, and Ubuntu still provides buggy versions of programs.