We know from history that the skill, wisdom and effort (and oodles of luck) needed to build and sustain a working democratic system (whatever you may think of the pros and cons of such a system is a separate and interesting discussion) in one of the ex-colonial countries is orders of magnitude greater than the skill needed to just run a functional government for a few years. Saddam, Gaddafi, Ayub Khan, they all ran functional regimes and even made their Universities conduct their examinations on time. But none had a system with adequate checks and balances or the mechanism to transfer power smoothly from one elite clique to another without having to shoot the other clique first.
It may be possible to repair the effects of poor governance by this or that democratic regime in a few years, but if the system as a whole is undermined and devalued, then it may never get working again, or may take decades to repair. Political authority (like money) is a shared (useful) illusion. Puncture the illusion and what is left is naked force (or, if enough of asabiya exists, a monarchy; whether called a monarchy or under some other name).