It only works if you have enough funds to make a working product or at least some beta version or MVP, otherwise, you have no options, except running an ICO or attracting investors.
Anyway, that's great if the team have a working product as in your case. This can really be a decisive advantage for some investors when choosing a project for investment.
Exactly, I really believe we will see a bigger shift toward working product approach as a lot of ICOs doesn't deliver what they promised. This approach should greatly contribute to blockchain adoption worldwide.