That's because many of the people who used Grails to build a website didn't intend sticking around to fix the bugs or maintain it -- they just wanted to get paid and move on to hawking themselves as experts in the next fashionable technology. Others chose Grails because they saw they could introduce loads of technical debt thus giving themselves an opportunity to charge a high hourly rate later on.

> I won't be making the Groovy mistake again any time soon

Oh, so you didn't choose Grails so you could skim an agent's fee from sourcing these people? Many did.