Culture add starts from the team as it is today and asks what is missing, whether that is a different professional background, a way of approaching problems or experience with a particular customer group. A hiring panel might notice that every engineer came through the same type of degree and look for someone who learned through an apprenticeship or a career change. Shared values still matter; the difference lies in perspective and experience.
Teams that hire only for sameness tend to deepen the same blind spots over time. Framing assessment around culture add pushes interviewers to name a concrete gap before the role opens, then score candidates against it. Writing that gap into the scorecard keeps it job-relevant and stops it becoming a loose label that can be bent to favour anyone.