All of the concepts discussed in this chapter are about making sure you are building something that customers will buy. And so, you must be careful to distinguish between random feedback and actual customer input. If you put a digital MVP out in the marketplace and then just start creating new features for every troll who gives you input, you'll be spinning your wheels. On the other hand, if ten people say they would buy your product now if you had one particular feature, that might be worth working on. My colleague Edwin Oh teaches an entire course on Product-Market Fit, and as he puts it:
"The only real validation is a monetary commitment in either the form of cash, a credit card number, a binding letter of intent, or dedication of resources to a beta test. Everything else is a pat on the back or an unqualified opinion." — Edwin Oh
So beware of making changes to your product based on an "unqualified opinion." Unqualified opinions don't pay the bills.
Remember also that there are many businesses where the user differs from the customer. Social media companies, for example, have users (you and me), and then they have customers (advertisers).
Two-sided marketplaces (discussed further in Week 4) need two sets of Product-Market Fit. Airbnb needed Product-Market Fit with people looking for a room to rent and also with people looking to get some income from the extra room in their house. With medical device startups, your user is the patient, but the customer actually making the purchase decision is often a physician (working within a purchase environment shaped by insurance companies). So, as you are working on getting to Product-Market Fit, ensure you are fitting all the right things!