I’m stunned by some projects where the community leader hasn’t undertaken a survey of members in years (and a handful where they have never collected feedback).
Their only inkling as to whether members are having a good community experience comes through the interactions of a handful of top members they engage with every day.
You should always be collecting feedback.
Do a survey once or twice a year. Find out how satisfied members are with the community, how relevant they find it to their work, and what aspects they do or don’t like. Use this to plot your priorities.
Try to interview a member at least once a week. Probe deep into what brings them to the community and why. What is and isn’t working for them. What would create a better experience? Use this to refine your personas.
Use polls to tackle more immediate questions about the kind of content and features members find most useful.