At the outset of a project or product kickoff, the User advocates should be at the table along with leadership stakeholders, content creation, marketing and development depending on the structure of your entity. This is the Discovery phase and crucial to finding out the motivations of your team, the initial user /customer groups and the basic business structure you will contend with during the complete cycle of making the experience being envisioned.
We can talk about the nuance of psychology, bias and enthusiastic ideation here but we'll leave that for a podcast or article. Suffice to say, this conception stage can reveal the very challenges your team will be dealing with as they carry forth and being a good listener is crucial.