Democracy indeed does improve decision-making in my opinion. The democratic process is one in which the will of the people is expressed in free and open elections where they choose leaders that best represent their interests. Such clear choices send a signal to leaders what it is the people want, and can make the appropriate decisions accordingly.
Democracy may not be the most efficient form of decision-making, but it allows for the greatest freedom of expression and debate over an issue. In a totalitarian state, for instance, alternate voices are not allowed to be heard, or people are afraid to voice alternate views for fear of punishment. When all sides of an issue are aired, as in a democracy, we have the greatest chance to reach a good decision.
The government best knows what to do. If people give their decisions to be looked over then there might be difficulty to the government to proceed with any particular matter which gets discussed. It's enough that the government looks over the matter on its own and make decision for the betterment of the country.