But the public policy domain is too multifaceted for that definition to be useful in practice. The very notion of coherence needs to be adapted to the realities of a complex environment, and to the practical capacities of policy-making systems. Governing in a democratic political system necessarily involves a degree of incoherence. Coherence is but one among several criteria of good governance in democratic societies, where governments are expected to be responsive to competing interests. Social and political factors bring into play an array of forces that rarely converge toward coherent sets of policies.
Interest groups seek to shape public policy in ways which, taken as a whole, serve disparate ends.
The information media can mobilise public opinion, and create expectations of quick governmental responses. Opinion polls bring contradictory short term pressures to bear on longer term policy direction. Seen in that light, good policy making is less a question of avoiding contradiction than one of managing it. This implies that policy-making systems must increase their capacity to balance and reconcile divergent pressures. No single policy-making system can guarantee improved coherence.