Second, data may not give you a deep understanding of people’s needs because you can only observe existing products. A simple example: You don’t know if users want a search functionality by looking at the data if there isn’t a search functionality in the first place.
If we think about asking people about our products, there’s a straightforward rule: Don’t ask stupid questions. The better you ask, the better answers you get. Also, what I especially believe: You have to make an effort. If you don’t have a good relationship with your users, they will lie to you, especially if you spread some uninspired online survey. Meet with people, talk to them in a relaxed environment, not in an interrogation-like setting. Trust is once again, the key ingredient to having qualitative results.