I think there are few reasons responsible for this problem, and a serious lack of any sort of infrastructure is a good one. The overwhelming majority of African nations lack even the most basic infrastructure such as highways and freeways, primary and secondary schools, colleges and universities, stable running water and electricity as well as clinics and hospitals. I think the governments of the various African nations are largely to blame as is mostly the case with all other reasons. The majority of African states have been independent for almost 60 years. What infrastructure have they developed through the 60 decades? Very little to none.
Education is also a major issue. A very large proportion of Africans is illiterate or possesses very basic education which is below a college or university degree or certificate. Illiteracy tends to cause people to be ignorant of most of the phenomena around them. This then in turn makes people to fail to realize how things are not the way they are supposed to be or envisioned to be. Basic or lack of education also causes people to become job-seekers instead of job-creators. That is why a large number of African move across countries (both in Africa and the rest of the world) just to find employment. But how can they get educated when there little or no education infrastructure? It leads back to point number one.
I have also noted that in most African nations, large-scale commercial agriculture is not practiced to its full potential. This is a detriment as it leads to the problem of food insecurity, crime and even potential conflict. There is a lot of land that is not used to its maximum capacity in Africa. Africans need to “evolve” past the stage of subsistence agriculture. It is just not sustainable anymore. We need to take advantage of the rising rate of urbanization and create employment in the agriculture sector instead of flocking to the cities to add to the list of job-seekers without actually thinking about who is supposed to create those jobs we are seeking.