The classic model of corporate governance is that the board of directors appoints and removes the principal corporate officers.  This is consistent with the general principle that the business and affairs of a corporation must be managed and all corporate powers be exercised by or under the direction of the board.  Cal. Corp. Code § 300(a).  

Appointment of officers by the board is not, however, written in stone (at least under the California General Corporation Law).  While Section 312(b) of the Corporations Code does indeed provide that "officers shall be chosen by the board and serve at the pleasure of the board", that statement is preceded by "[e]xcept as otherwise provided by the articles or bylaws".   This leads to the possibility of the articles or bylaws providing for election and/or removal of officers by the shareholders.

Nevada's private corporation law similarly allows the bylaws to provide for the manner of choosing officers:

All officers must be natural persons and must be chosen in such manner, hold their offices for such terms and have such powers and duties as may be prescribed by the bylaws or determined by the board of directors. 

NRS 78. 130(3).

Allowing shareholders to choose corporate officers is difficult to square with the board's ultimate management responsibilities.  How can a board manage the business and affairs of the corporation, if it has no authority to appoint and/or remove officers?  

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