[@mention:549200391377900110] It's true that it's not obvious and could be clearer (you can propose improvements here!) But the key is in the constitution.
Several rules of the constitution are tied to the Secretary or, to use [@mention:450819477777465353]'s example, to the Lead Link.
For example, a governance meeting is only valid if the Secretary has called it:
3.3.2 Notice & Quorum
A Circle may only conduct its Governance Process in a meeting if the Secretary has given all Core Circle Members reasonable advance notice that a Governance Meeting will be held, including its time and location.
Or metrics are only required if the Lead Link has assigned them:
4.1.1 Duty of Transparency
... (d) Checklist Items & Metrics: ... You must also track and report on any metrics assigned to your Roles by the Circle’s Lead Link, or by any other Role or process granted the authority to define the Circle’s metrics.