The reasons for conversion are the same reasons an LLC might be the best selection at the time a business entity is initially created. The LLC form will generally allow the separation of decision making from equity. In the corporate form, s shareholder has one vote per share to elect directors, with the directors in turn selecting officers. In the LLC form, there is no automatic tie in of equity and control.
Corporate shares are subject to seizure and sale upon execution by the sheriff.
In some states, like Texas, annual meetings are not required. What I don't understand is what advantage is gained in converting a C corp to an LLC for state law purposes but retaining C corp status for federal income tax purposes.