Not even that: directors are required to act in the interests of the company. Acting in the interests of shareholders is problematic, as different shareholders

Not even that: directors are required to act in the interests of the company. Acting in the interests of shareholders is problematic, as different shareholders have different interests (especially minority vs majority). And by keeping the duty to act in the interests of the company, directors are not required to focus on short-term profitability and shareholder dividends; decisions can be justified as being in the long-term interests of the company, and better for the company's reputation and culture, even if they don't deliver shareholders the maximum short-term gains.