There are different implementations of Democracy, but I don’t know of one that merits the name. For example, the people should have the right of veto and they don’t! In business, if you allowed the boss to continue making a mess of things for 5 years then it would be regarded as very bad management. Obviously not being able to get rid of an elected person for 5 years is also very bad management, especially as they are running the country! Then there is the other side of the problem. If the elcted one won by 45% of the vote then who is representing the other 55%? In practice, the answer is nobody!

That having been said, what advantage does a Dictatorship (I also include a Junta under that heading) offer? That appears to be entirely related to the kind of person who assumes that power. If they really want to do the best for their people, then that is very good and would be superior to Democracy for the reasons you cited.

Semetimes there is a mddle road. For example, in Thailand the Army have taken over, but only to stop a civil war, ditto in Egypt. In short it all seesm to depend upon the motivation of the Dictator, which is not necessarily known before hand.