Lant Pritchett makes an excellent point that building capacity and getting things done are sometimes in conflict.
A third common flaw in development efforts is to “cocoon” projects from the normal channels of implementation. If one feels very strongly that something needs to be done and one knows that the existing national mechanisms are to weak to do it, there is a temptation to bring in foreign contractors and import the capability. Given the resources and capabilities of American government and contracting firms, of course many things can be done quickly. But this usually not just does not build capability, it both undermines the building of national capability and does not improve a government’s legitimacy. Moreover, this gets done at costs that are astronomical relative to what the national government could ever hope to afford. At one point great claims were being made about the improvements in the health sector and health outcomes in Afghanistan. Even if we grant those were major and important gains, since it was being done by American contractors it meant an Afghan doctor could make many-fold more income working as a driver for the health project than he could as a doctor in a regular government clinic. Back of the envelope calculations were that the cost per person of the health system exceeded not just the potential total government expenditure per person but total post-withdrawal GDP per capita.
The context is Afghanistan but the point is widely applicable in development economics and also to say child development.
Addendum: See also my paper with Shruti, on Premature Imitation and India’s Flailing State.