Upvote:3
Both Nigeria and Kenya had seen limited forms of self-government before independence.
For example, Nigeria's first post-independence President, Nnamdi Azikiwe, had previously been a journalist and publisher and then a politician and colonial Governor-General, while its first Prime Minister Abubakar Tafawa Balewa had previously been a teacher and school inspector and then a politician and government minister.
Meanwhile in Kenya, the first post-independence Prime Minister and a year later its first President, Jomo Kenyatta, had a university education at the London School of Economics and then became a politician, being imprisoned by the British during the Mau Mau uprising but after his release being elected to the Legislative Council.
So in both these cases, and in many similar cases across the British Empire, many of the leadership immediately post-independence had political and government experience before independence. The same was the case in much of the French Empire, and in both cases there were also some attempts to educate an indigenous professional class, notably in universities in London and Paris.
Upvote:4
It's a strangely consequentialist way to look at these events. The independence of the DRC was a part of a larger movement and I would guess that its leaders regarded it as a basic necessity, not something you could choose to give up or postpone because the circumstances are not the best.
Beyond that, the general lack of any sort of trained elite and local bureaucracy wasn't something Congo shared with other African countries so your question touches upon a very important aspect of the history of the country. In fact, it was a direct result of Belgian mismanagement and the cynical calculation that making independence as difficult as possible would prompt the Congolese to come back to them.
For all their faults, neither the French nor the British did the same. Even the Portuguese - who resisted the independence movements with everything they had - provided a relatively effective and broad (basic) education to the local people.