Each individual can, as a man, have a private will contrary to or different from the general will that he has as a citizen. His private interest can speak to him in an entirely different manner than the common interest.
Gist of Idea
Individual citizens still retain a private will, which may be contrary to the general will
Jean-Jacques Rousseau (The Social Contract (tr Cress) , I.7)
So why I accept the general will when these two clash (apart from threat of punishment - which may be capital if I am recalcitrant!)? Usually the general will is also for my good - but not always. Idealist love of the people?
Rousseau,Jean-Jacques: 'The Basic Political Writings', ed/tr. Cress,Donald A. [Hackett 1987], p.150