Because opinions differ among experts, democracies tend to prefer committees in which decisions are made by discussion among the experts--and, in many cases, other representatives of the public--who discuss, try to persuade each other, and must at the end of their deliberations reach a decision.
But those decisions have to be explained to the public and to other parts of the government--and hence the appropriate emphasis on transparency and accountability. That is the democratic way of making decisions when opinions differ, as they often do in the monetary field.