No, it is up to the coherent extrapolated volition[1] of the dictator's people. (At least, it seems like a good guess.) What makes a government less than ideal is its failure to apply that volition. The question then is how hard a given type of governance is likely to fail.
Now I agree that for a host of reasons (like taking one's own volition for the country's CEV), dictatorships do not rank high.