More than a bean counter
When people ask me the role of a CFO, I tell them it has two aspects:
1. Saying NO. No to hair brained schemes, no to spending too much money, no to budgets and plans that are not grounded in reality
2. Being the ethical center of the company. Grounding that company in ethical behavior that minimize or precludes the company from either breaking the law of being sued.
This article on Theranos confirms my view of my role.