From my perspective business depends on both idea and product/ service. i will make my statement clear with a short example:
I have an idea to open a book café its a concept that's gaining popularity recently. The idea will be accepted by my customer. But if i have poor quality foods or books there or the servers are rule or unfriendly I will lose my customers.
Another scenario my product and service both is good but the book café is too common and available then my idea won't give me much benefit.