If you could distill all of the advice from all the popular self-help and productivity books on the market today into one word it would probably be focus. Focus on what's important. Focus on pleasing your customers. Focus on doing what you do well. One-word productivity books don't sell very well, though, but that seems to be at the core of everything from David Allen's Getting Things Done to Seth Godin's Linchpin.
Of course I'm over-simplifying, but focus is enormously important, especially for resource-constrained organizations. That describes startups and most open source projects. So I found Steve Bank's Death by Competitive Analysis particularly compelling.
Competitive analysis is looking at the market and seeing how you stack up against the competition. These are usually considered good because if you're looking at the competition (say, Microsoft Word) then you want to find out what features your project needs to have to be successful.
Banks argues that this is the wrong approach, and organizations (and I would add FLOSS projects) need to focus on a minimum feature set they can do very well:
At its best a competitive analysis assumes that you know why customers are going to buy your product. At its worst it exists to rationalize the founder's assumptions about what they are building. This is a mistake - and it is a contributing factor (if not a root cause) of why most startups get their initial feature set wrong.
If you are building a competitive analysis table, do so only after you understand that the features you are listing matter to customers. Most marketers are happy to build feature comparisons. But customers don't buy features, they usually buy something that solves a real or perceived need. That's the comparison you and your investors should be looking at - what do customers say they need or want?
In other words, rather than looking at Word and suffering feature envy, OpenOffice.org (not to pick on anyone in particular, I just chose Word as the most feature-laden product most folks are familiar with) should be polling its users and potential users and asking what do you need or want from a word processor?
Most FLOSS projects are resource-constrained, and can only really afford to focus on a limited feature set rather than trying to deliver every feature ever conceived. The successful ones, typically, are those that focus and deliver the minimum feature set but do it very well.