First, see through the lens of what the user needs

A lot of failures around shipping a new feature or even launching an entirely new product is the loss of focus in knowing what motivates the user. Knowing what motivates your users is vital in knowing how your product, what it does & doesn't do.

Start with asking

This sounds obvious, but it's often easy to assume a lot about the people who you are building the product for, especially across big teams or for new members that join. User interviews are the best place to start in defining the motivators across your user types.

What people say and what people do are two different things.

Ask someone to describe their dream house, they'll talk about Italian marble, the beautiful oak cabinets, the feature-lights and incredible mountain view. What they won't mention is that they have a door and plumbing with hot and cold. These are the obvious 'must-have' things. They're vital. Without them, you have no users. Additionally, some users will reject and loathe an update - Facebook, for example, made an enormous change to their UI in 2010. People vowed to leave, that it was the end of the social giant. The reality is, they kept using the product. What people say, and what they do, are often two very different things.