There are lots of non-governmental organisations (NGOs) working in the Great Lakes region, offering lots of jobs. Some of these jobs pay well and offer benefits that are not available in other positions in the region. For example, in Rwanda the World Food Program "offers a competitive compensation package which will be determined by the contract type and selected candidate’s qualifications and experience", while the International Organization for Migration (IOM) is offering a salary to a driver of "G2/1 (UN Salary Scale for GS staff)", which I think is worth Rwandan Franc 6,885,000 per year, or about 10,000 US dollars or EU Euros. As the rewards of NGO work seem appealing, people who might otherwise go into the private or government sector may instead prefer to work in NGOs. The One Acre Fund, an agricultural NGO, claims to be Rwanda's fastest growing professional organisation.
There's some evidence that people are showing more interest in the relatively high paying NGO jobs. The site www.jobinrwanda.com lists job advertisements in Rwanda from NGOs, the private sector, and the state sector. It also says how many times people have looked at each job advertisement. For the IOM position, which was posted on 17 April, there have been 2438 views at the time of writing. By comparison the views for private and government jobs have been generally, but not always, lower: numeracy materials developer (22 April, 360 views), bush camp host (1 April, 610 views), network engineer (21 April, 1579 views), receptionist (14 April, 2481 views), and monitoring officer (22 April, 465 views). Other recent NGO advertisements have attracted many views: Africa Humanitarian Action (3262 views), World Food Program (1826 views), and One Acre Fund (1171 views).
There are many different ways of looking at the attraction of NGO jobs from an economic viewpoint. People are diverted from non-NGO occupations where they may have higher economic output or output growth, particularly in the private sector where there is greater competition to please consumers directly. NGOs may be productive and contribute to economic growth, but these outcomes are not usually their prime goal, and not generally enforced by the threat of closure.
Foreign NGO wages increase the amount of money in the Rwandan economy. They act as an injection into the economy, in the dominant Keynesian macroeconomic model: much of the wages gets spent in Rwanda, making other people and companies richer, who spend much of their money in Rwanda, and the circle continues. So the wages can increase the national income by an amount exceeding their initial level.
NGO wages probably don't have the potential for growth that private sector jobs do. Rwanda - capitalist, fairly free of corruption, growing rapidly, integrated in the wider East African economy - will offer an increasing number of private sector opportunities to become very rich through skill, persistence, and luck. The NGO sector offers immediate rewards, but probably far fewer growth prospects.
If I was ambitious in Rwanda and without too many family or personal responsibilities, it would be the private sector that would attract me, with its possibly lower wages and harder work in the short run.