So what went wrong with MySQL 5.1 ?
 
This is surprisingly not because our developers don't do a good job. On the contrary we have an excellent dedicated team of developers that are very good in what they are doing. However, even an excellent team can't work if the conditions are not right.
 
Here follows some of the main reasons why MySQL development department again got a quality problem with a GA release:
 

• MySQL 5.1 was declared beta and RC way too early. The reason MySQL 5.1 was declared RC was not because we thought it was close to being GA, but because the MySQL manager in charge *wanted to get more people testing MySQL 5.1*. This didn't however help much, which is proved by the fact that it has taken us 14 months and 7 RC's before we could do the current "GA". This caused problems for developers as MySQL developers have not been able to do any larger changes in the source code since February 2006!
• We have changed the release model so that instead of focusing on quality and features our release is now defined by timeliness and features. Quality is not regarded to be that important. To quote Mårten Mickos: "MySQL 5.1 will be release as GA in or before December because I say so". Mårten's reasons for this is that he needs something he can sell and a release marked "GA" is much easier to sell than a release marked "RC".
• The MySQL core developers have been split into too many teams and only a small part of the core developers have been working on MySQL 5.1 to get the bugs fixed. Some of the core developers have also recently left the MySQL organization which is a serious issue as there is not many of of them.
• Too many new developers without a thorough knowledge of the server have been put on the product trying to fix bugs. This in combined with a failing review process have introduced of a lot new bugs while trying to fix old bugs.
• Bug fixing and development processes are not systematic and not persistent.
• We have not been giving the MySQL community enough opportunities to test MySQL 5.1 (too few releases). The reason few releases was made was that if we would have done a release every month, as we have done in the past, we would have got 14 RC releases which would have looked silly and proved that the first RC was made too early. In addition, the MySQL current development model doesn't in practice allow the MySQL community to participate in the development of the MySQL server.
• The MySQL organization doesn't have a release criteria for the MySQL server that is followed; Both the external one and the internal one have not been followed when it comes to declaring MySQL 5.1 as GA. You can read more about our release policy in Kaj's blog.
• Internal QA on the MySQL server was started very late in the process. Now when the process have started to show results, the found bugs have largely being ignored as fixing these they would delayed the MySQL 5.1 GA date.
• The MySQL server team have a bug fixing policy where a bug that has existed a long time has a lower priority 'because people know about them'. This is supposedly one of the reasons why the Bug#989 mentioned above has not been fixed.

One would have thought that MySQL AB (now the MySQL department at Sun) should have learned something from our too early release of MySQL 5.0 but unfortunately this is not the case. The main argument I have heard for why MySQL 5.1 was declared as GA now is that it's better than MySQL 5.0 was when it was declared as GA. In my opinion, this is not a good reason to declare something GA, especially as 5.0 GA was in terrible shape when it was released. What is worse is that the new features in MySQL 5.1 are of no better quality than new features in MySQL 5.0 was at the time MySQL 5.0 was declared GA.

The ugly part was of course the announcement that MySQL was planning to change the MySQL server from open source/free software to crippleware by only giving out key parts of MySQL online backup (a server component) as closed source within the Enterprise server offering.
(...)
My second talk "Future Design Hurdles to Tackle in the MySQL Server" or "The Future of MySQL (The Project)" was even better received. During the talk we had spontaneous chanting of "We don't ship crippleware" and afterwards I got many people coming to say to me that it was my best talk ever! (This doesn't of course say anything else than that I may be improving or that they have never heard me present before)

I experienced something I’d never seen before in Britain the other day. I ordered a cup of tea in a pub and was served with a cup of hot water with the teabag on the side. I’ve seen this in other, less self-respecting countries, but never in tea’s spiritual heartland. Tea is made by pouring freshly drawn boiling water over tealeaves. If someone serves you warm water with the tea on the side, they have not accurately filled your order of a cup of tea.
 
Of course, the serving staff at the pub were all foreigners, and I had to educate them on how to properly make a cup of tea. They were very grateful for the lesson, but gamely disguised their gratitude so as not to embarrass me. But the damage was done. I was served hot water in a British pub, and there is simply no coming back from that. Needless to say, within 48 hours I had boarded an aeroplane and left the country in disgust.