How many people should be accountable for a process as defined in the RACI model?

Having as many people as necessary applies to the 'R' - Responsible - role in RACI, where multiple people can carry out the work, but accountability is always restricted to exactly one individual.

In the RACI model, the 'A' - Accountable - designation must be assigned to exactly one person per process or activity, and in ITIL that person is the process owner. This single-accountability rule exists to ensure there is always one identifiable decision-maker who is ultimately answerable for the outcome. Assigning accountability to more than one person undermines the governance purpose of the model.

RACI explicitly limits accountability to one person per activity; assigning it to two people - regardless of their titles - violates the core rule and creates ambiguity over who is ultimately answerable.

A process architect may design the process but does not necessarily hold accountability for it; the RACI model assigns accountability to the process owner, not to the architect role.