Well, this is pretty simple.
The reason a Dictatorship is the best form of government is obviously because it allows one man to control everything. Now, as long as this one man is a good person, in fact perfect, then this dictatorship will be the best ever.
Now, as this doesn't really happen, dictatorships don't really work out. This applies to all forms of government, communism, socialism etc. At their core, they have good ideas, which is what persuades many people of good intent that they are in fact the best form of government.
However, because most people are at some level corrupt, a democracy ends up being the best form of government. It has many problems don't get me wrong, but it puts the decisions that are made essentially into many hands, so that way their are checks and balances.
The saying that applies to this is "Their is always one bad apple in a barrel". Hopefully all the good apples will outweigh the few bad.
Hope you guys like what i had to say.
Smurf.