Sales or Development - The chicken or the egg?

I got in an interesting conversation tonight with a friend of mine that works as a sales rep.  We were talking about his job, and we somehow got on the topic of how important the product is to a salesperson.  His claim was that the product is completely irrelevant to a salesperson because you can either sell or you can't and it's not actually about what you're selling.

Obviously this is ridiculous, but I want to discuss it anyway because it leads to some other thoughts.  First, saying "a salesperson can sell" seems eerily similar to baseball fans saying that a good pitcher knows how to win games.  If a pitcher's team doesn't score any runs, the pitcher may very well lose despite throwing an amazing game.  There's some sort of weird jock logic that makes people think "winners win" and I believe it's the same attitude that leads someone to believe they can sell regardless of the product.

If we look at this from a developer's point of view, it would be possible to take a similarly naive position.  I can create great software regardless of what the marketing and sales people do.  I can make a product great so there's no reason to care about sales or marketing.  It's true that the product can be great, but what's the point of making a great product if you can't sell it?

So I think we can all agree that a salesperson can't sell a product that doesn't exist and there's no point in a developer create a product that has no way of being distributed.  Similarly, HR, operations, and IT are all important.  However, most start-up companies (particularly those that bootstrap like we do) are short on resources and have to pick one or two core competencies.  When deciding between development and sales, what should a company focus on?

Well, while there's no question both are needed equally (for most companies), that doesn't mean that you can't easily decide which comes first.  This is not a "chicken or the egg" situation.  Obviously, you develop a product first, and then you sell it.  When a company is getting started, it's worth thinking about marketing and sales, but it would be ridiculous to prioritize either of those areas above development until you actually have a product to sell.