Canonical may not see Ubuntu as having the luxury of waiting until everyone on the internet deems it's "fit for end users", because their competitors haven't. Microsoft never waited until DOS or Windows were perfected, they just released them once they thought they were adequate, and the standard advice there forever has been to do a full reinstall of the system rather than an in-place upgrade.
"Microsoft never waited until DOS or Windows were perfected, they just released them once they thought they were adequate"
NEVER WAITED??? I bet you were too young to remember those days because Micorsoft(Bill Gates) promised Windows(3.11) like 6 years before it was ready. Windows was coming "soon", and "soon" and "soon", for years.
And better we don't talk about DOS. DRDOS was much better than MSDOS, but MS made windows over DRDOS so they had not to compete on technical merits.
