No one thing can guarantee success in a startup. For a startup to succeed, 20 things have to go well. For it to fail, one thing has to break.
Of course you need a good business model. But that itself will be of no use if the product is not good. The product will not be bought if the communication is not right. The product will not reach the customer if the distribution is not right. And there are a number of such interdependent things that contribute to success.
By the way, there is not one ‘winning business model’. A business model is a strategic choice you make. And strategy is about choosing from the MANY options you have available to choose from, and then aligning the rest of the organization around that decision.