Here's what I have found in my 15 years of helping startups raise investor funding:
The business plan of a fundable company has enough of the right stuff in five main factors: product viability, business model, market strategy, management, and the deal. If you fall short in one or more of these factors, investors won't take you seriously. To check the fundability of your startup, take my free Minimum Fundable Company
test at www.mfctest.com
Then, once you cross this threshold, investors make their decisions based on their belief in your business concept and how likeable and trustworthy you are.