Why a startup's initial business plan doesn't matter that much

A startup's initial business plan doesn't matter that much, because it is very hard to determine up front exactly what combination of product and market will result in success.

By definition you will be doing something new, in a world that is a very uncertain place. You are simply probably not going to know whether your initial idea will work as a product and a business, or not. And you will probably have to rapidly evolve your plan -- possibly every aspect of it -- as you go.

(The military has a saying that expresses the same concept -- "No battle plan ever survives contact with the enemy." In this case, your enemy is the world at large.)

It is therefore much more important for a startup to aggressively seek out a big market, and product/market fit within that market, once the startup is up and running, than it is to try to plan out what you are going to do in great detail ahead of time.

(via Marc Andreessen's Blog pmarca: http://blog.pmarca.com/2007/07/why-a-startups-.html)

Excellent post that makes a point why it is so difficult to plan ahead for a start-up. Your initial idea might be great but you might find that there's no market at all, you're too early or too late, you haven't got the ressources to establish your business in the marketplace or you just find another approach on how to build your business.