In a democracy there exists a political market; politicians chase votes and electors chase government largesse. It is a myth that politicians promote the general interest; they are primarily interested in gaining and holding political office; it is power they seek. It is the political market that drives politically interested people to create and accommodate a coalition of special interests rather than the general interest. A quote from Walter Lippmann will illustrate the point:

"In government offices which are sensitive to the vehemence and passion of mass sentiment public men have no sure tenure. They are in effect perpetual office seekers, always on trial for their political lives, always required to court their restless constituents. They are deprived of their independence. Democratic politicians rarely feel they can afford the luxury of telling the whole truth to the people. And since not telling it, though prudent, is uncomfortable, they find it easier if they themselves do not have to hear too often too much of the sour truth. The men under them who report and collect the news come to realize in their turn that it is safer to be wrong before it has become fashionable to be right.
With exceptions so rare that they are regarded as miracles and freaks of nature, successful democratic politicians are insecure and intimidated men. They advance politically only as they placate, appease, bribe, seduce, bamboozle, or otherwise manage to manipulate the demanding and threatening elements in their constituencies. The decisive consideration is not whether the proposition is good but whether it is popular - not whether it will work well and prove itself but whether the active talking constituents like it immediately. Politicians rationalize this servitude by saying that in a democracy public men are the servants of the people.
This devitalization of the governing power is the malady of democratic states. As the malady grows the executives become highly susceptible to the encroachment and usurpation by elected assemblies; they are pressed and harassed by the higgling of parties, by the agents of organized interests, and by the spokesmen of sectarians and ideologues. The malady can be fatal. It can be deadly to the very survival of the state as a free society if, when the great and hard issues of war and peace, of security and solvency, of revolution and order are up for decision, the executive and judicial departments, with their civil servants and technicians, have lost their power to decide."2