HubSpot pricing for many plans is based partly on seats. Users who need paid features, such as sequences, the forecast tool or the help desk, are assigned the right seat type, while others can be given free access with fewer features. Seat types and what they include depend on your subscription.
Inactive users cost money in two ways. A paid seat assigned to someone who no longer logs in is spend with no return. And every user who still has access is a security risk, especially former employees or contractors who kept their login after leaving. If those users have broad permissions or super admin access, the risk is larger.
Low usage is also a signal. If many people with paid seats rarely log in, either they do not need HubSpot for their job, or the setup is not working for them. Both are worth knowing before a renewal.
Review users every quarter. Deactivate people who have left, move inactive users to free access or remove them, reassign the records they own, and check that offboarding includes removing HubSpot access on the last day.