Need help on What kind of startup do you want it to be?

Under this title the writer is trying to say that the kind of startup needs to be thought of. I've read it multiple times but I don't get it why is it important to decide on the type of startup. https://www.amazon.in/dp/B00TACMNTU/ref=pe_386221_57731711_pe_520732_50917562M1DP Can someone please help me understand why is it important to decide on the type of startup?