I read that theory multiple times, and on the surface it makes sense, e. g. corrupt oligarchs siphoning away money. But there are countries in Africa not governed by a dictatorship; I think a small country in west/middle Africa led by a woman some years ago. And they still found it close to impossible to break out of the poverty circle. You also can not easily compete with richer countries - they pump more money into their production while also swarming the local market with somewhat semi-affordable stuff that gets subvention from home. You need to re-think the local economy first and foremost and fix that. Granted, that's harder when dictators seize power, getting their weapons from outside factors, but I think it is possible to solve that problem too.