Dismissal [...] should be used rarely in order to preserve the greatest diversity on the Council.

But later...

each dismissal is decided by simple majority of those not abstaining.

If dismissal is supposed to be so rare, why is it not a decision with a higher bar (e.g., supermajority)?

The underlying concern here is that a close vote appears more contentious / political, and might affect the legitimacy of any decisions that the resulting Council makes.