My reasoning:

Incentives for decisions:

The person most capable of making impartial decisions in a country is someone isolated from its consequences. Someone who won't become poorer if government spending is cut, and who won't become richer if government spending increases. This person should have no material wants. A person with unlimited money and possessions cannot be bribed, they can't abuse power to enrich themselves. By definition they own everything in the country. So what does a person with no material desires desire? They desire a legacy. Someone who's personal legacy is tied to the success of the country as a whole, not the prosperity of groups or organizations within it, will make the best decisions. The incentives become purely the success of the nation as a whole. How wealthy and prosperous its people are, how beautiful its cities are, how clean its water is, how impressive its conquests are.

Decision Making Ability:

The average person has zero understanding of how to utilize government to achieve goals. They have desires only. "I want to have higher pay". They have even less understanding of geopolitics and foreign policy. A dictator is produced in two ways. Either they seized power by force, or they are the child of the previous dictator. Both of these have very high likelihood of being competent knowledgeable and effective leaders. If they seized power by force they clearly are extremely competent and capable with a good understanding of how the country works. If they are the child of a dictator they would have grown up observing and being trained in statecraft. By the time their father steps down they would have a wealth of experience, and would have learned from their father's mistakes and formed their own ideas on what to improve.

Power to mobilize resources and make long term decisions:

Most people understand the main benefit of a dictator is the ability to mobilize resources to achieve a nation's goals without gridlock or obstructions. Ultimate power. But another benefit is the ability to act long term. What if a debt crisis will take 10 years to solve, and for those 10 years there will be significant hardship to an influential group like the nation's elite or the nation's poorest? In a democracy the elites would fund campaign ads, the poor would have mass protests, the leader would be immediately voted out at the next election, and the needed austerity wouldn't happen. The debt crisis would continue. A dictator can pursue long term goals without worrying about short term consequences.

Abuse and Accountability:

A dictator is not immune. They are protected from an unhappy populace in the short term which is important for making tough but necessary decisions, but every dictator knows that the consequences of failure are not simply losing an election and going home, but being dragged from your palace and beaten to death by an angry mob. This fear is always in the back of their minds, and acts as a check on their power.