Ubuntu 12.04's build failures addressed immediately
Ubuntu 12.04 is definitely an LTS, not only because is released on a two years cadence, but also the commitments to stability and "everything must work".
Precise has adopted an automated test, Jenkins, that stresses the daily builds in order to strengthen them, obviously logging the errors.
What is interesting about Precise's automated test is the response to failures in terms of hours, not days.
Ubuntu's Engineering director, Rick Spencer, stated few days ago that every issue in the Ubuntu daily builds must be addressed immediately, tests that are available at https://jenkins.qa.ubuntu.com/view/Precise/ , where one can see detailed informations about various Ubuntu flavors, crashes, Last Success, Last Failure, etc.
The importance of this tests,from the user point-of-view, is that if a build is successful on the above mentioned site, then it should be installable on a machine.