What is the business judgment rule for a director of a corporation?

"The business judgment rule is premised on the notion that management of the corporation is best left to those to whom it has been entrusted, not to the courts. [Citation.] The rule requires judicial deference to the business judgment of corporate directors so long as there is no fraud or breach of trust, and no conflict of interest exists. [Citations.] The rule has been codified in section 309, which requires a director to perform 'in good faith, in a manner such director believes to be in the best interests of the corporation and its shareholders and with such care, including reasonable inquiry, as an ordinarily prudent person in a like position would use under similar circumstances.' " (Desaigoudar v. Meyercord (2003) 108 Cal.App.4th 173, 183, footnotes omitted.)