There's a place for every approach and the one you mention works well in many situations. Look at Apple! However, Lean handles one of the great problems with t

There's a place for every approach and the one you mention works well in many situations. Look at Apple! However, Lean handles one of the great problems with this one (which is quite traditional as aytekin has already pointed out): it can take more resources than your typical startup might have. Sure, they can raise capital somehow, but that too could require more resources than are available. Often, an entrepreneur will want to start from scratch, and may have no experience building a product or a business. That's where the Lean Startup approach does well.