An answer from a new World Bank paper :
Rural poverty is increasing. The growth trajectory, while respectable, is not sufficient to reach the government’s objective of achieving middle-income status by 2030. There is an urgent need to increase the productivity of both the formal and informal sectors.Why does this situation persist? Political economists point to many contributing factors: the rent-seeking behavior typical of many land-locked countries rich in natural resources; the legacy of socialism that encouraged over-reliance on the state as the engine of employment and economic growth; the volatility associated with reliance on a single commodity market; high poverty levels; and the lack of a civic voice, especially among the rural poor. Zambia manifests some key features of what has been described as a Limited Access Order (LAO). In the LAO, elites trade economic rents for political support; hence they tend to resist reforms that could detract from their financial and political dominance.To the extent that this is true, then Zambia would seem to be caught in a vicious circle. Rents are important (due to the importance of the mining industry and aggravated by the fact that the country is landlocked), and the lack of economic/trade diversification allows capture and rent-seeking behavior to prosper. This phenomenon perpetuates the status quo (wherein many sectors seem to be captured by monopolies or cartels), which, in turn, limits productivity, economic diversification, and the formation of new businesses.
This assessment of course is in line with our previous assessment that economic outcomes are fundamentally about allocation of political and economic power. To the extent that people in power have no incentive to change the distribution of political power, they will continue to pursue economic policies that keeps them dominant politically. For example, they will seek to control loss making media houses; maintain parastatals as cash cows at the expense of genuine competition; pander to foreign corporations at the expense of locals because such firms finance their campaigns; and, only undertake development when they are politically vulnerable. In short, its not that policy makers are ignorant about the necessary solutions to move Zambia forward, rather there's an inherent lack of will on their part (incentives) to pursue that which they know is in the interests of the greater majority. We are poor because our poverty serves the elites that rule Zambia.