There is outsourcing to Africa. It’s just not us that is doing it. China has been in the practice, for a while, of offshoring industries that are being phased out of the Chinese economy. Leatherwork is a big one- it’s messy, labor intensive, and just not anyone’s first choice of business. China’s labor force is becoming educated enough that leatherwork factories cannot make a profit after paying salaries. So Chinese companies are moving their leatherwork capacity to Africa, where they make pretty low margins, but more than nothing.
Chinese investors historically are willing to invest in enterprises that most developed-world investors consider too marginal to bother with. China long didn’t have access to the first-rate opportunities, so they became used to the idea of squeezing what they could out of low-profit enterprises. It helps that many Chinese people are used to similar living conditions as their African counterparts. Americans supervisors in offshoring operations expect cars with drivers, nice houses in a gated expat community, access to first-rate private schools, etc. Chinese people working in Africa often live about on par with middle-class Africans, which is not a horrible way to live, but doesn’t include perks like back of generators and Landcruisers.
The factors you listed are good, and I’d like to add one big one- education. India and China both have huge pools of people from internationally-recognized universities. They don’t just have the raw labor, but also the supervisors and managers. Why is this?
India has had, since at least the days of the Raj, an educated bureaucratic class. Britain saw India not as a mine, but as a market for British goods. Their big plan was to take raw materials from India, process them in Britain, and then sell it back to the Indian population, creating profit at every step. To be a decent market, you need a middle class. So Britain colonized in a way that created a that middle class. In the course of doing this, they set up a pretty functional education system, complete with competitive universities. And they had government jobs for people coming out of this education system. The British Colonial bureaucracy in India was heavily populated with educated Indian bureaucrats.
African colonization was a different story. Africa was seen as a mine, not a market. This may simply be because the toll of malaria made it impossible to get enough Europeans out there to make it worth developing as a colony. Outside of the most temperate and malaria free areas, African colonialism was a set of outposts, not a functioning (if extremely unfair) government like the Raj. Rule was indirect- Colonial powers offered weapons and support to local leaders. In exchange for this right to rule their area, the local leaders paid a set amount of taxes, often in natural resources or labor. A leader who failed to meet his quota was not educated or trained, but rather his rival was given some weapons and a chance to rule for a while. The few attempts to train a political class were limited to shipping off a round of kids to Paris universities now and then.
Please do not forget how recent this was. This 1962 Time magazine article is one of my favorites. It outlines the new countries of Africa, including how many educated people they have. Most countries had less than one hundred college graduates, anywhere in the country. Some places were starting a country with less than ten people holding bachelors degrees.
They just haven’t had the time to build the education it takes to compete globally. It’s coming, but it will take a while.
I think the other biggies are unstable, “nationalization” happy governments that make it difficult to run a lot of businesses, serious infrastructure and transportation problems, poor internet connectivity (even in South Africa big cities, it isn’t great) and difficult-to-impossible tax codes and legal regulations on business.