1. RIM is a Canadian company, and from my experience (as a Canadian who went to school in Waterloo), Canadian companies like management - they are incredibly top heavy. This is especially true in the case of RIM - my friends there tell horror stories of how hard it is to make changes or even coordinate between teams. In contrast, I've found American companies err almost too far on the other side - not enough management to give some structure. So you have a lot of people who delegate, and not many people to actually do things, and nobody to organize the mess. Three bosses? I think yes.
2. They also don't pay very well. Out of school, my offer from RIM as a software developer was just over half of the offers I got from Microsoft, Amazon and co. So they're not getting the A team, or the B team, or really even the C team. To be fair, Waterloo is not nearly as expensive as Seattle or San Francisco, but still, as a whole they end up with the developers who are either unambitious (this is the best case, because many of these people are very smart), or just not very hard working. There are a lot of "retirees" too - people who want the 9-5 to raise a family (which is not itself bad, but you can't have an entire company made up of people like that). So basically, a whole lot of apathy.
3. There's a culture there of yes men. Look at how Laz ran the show - basically, it was a culture of denial that the iPhone even existed (look up some quotes from him about the iPhone from 2007 - 2009). Their product cycle has always been twice as long as the rest of the industry (and when they do, it's often incredibly half baked). While I think that Heins is really smart, and I certainly wouldn't want his job, he's stepped into a really broken culture. Their heads have been in the sand for ages.
4. If their public APIs/development chain are indicative of their internal workings, it's a mess over there - no wonder they can't ship anything. No documentation, poorly build APIs, and an awful, awful simulator (although to be fair, the last time I worked with BlackBerry's APIs was right after the iPhone came out, so they may have improved). It's a mess.
5. The ship is sinking! Anyone who can get a job elsewhere is going to get out as soon as they can. And why would people crunch to get the project out the door, if they think that they are going to get laid off anyway in six months? Nobody's getting raises, nobody's getting bonuses.
I would love for RIM to succeed, but it's much more than the market that is holding them back.