The point in this piece about getting out of the building and physically talking to customers is a good one. YCombinator tells their companies to do things that don’t scale at early stages. Knocking on doors and cold calling customers is something that doesn’t scale. But, if you know how to structure a sales call, the company can benefit.
In this high tech age, investors place a high value on technical skills. They won’t back a company without a technical co-founder. At the same time, even if a better mousetrap is built, someone has to sell it. Marketing, and selling to customers is just as important as engineering. Besides, the best form of investment capital you can find is top line revenue!