There is and will never be, that any nation has or will achieve any scientific, technical or technological advancement through the deployment of foreigners. A nation can only advance through its own human resources. Nigerians in fields of STEM are all toiling in developed and developing nations of the world because they are good or wanted in Nigeria for one stupid reason or the other. President Buhari has visited Germany for than twice and has never made any attempt to see the nigerians in these STEM branch. Could be he has been told that there are no such qualified nigerians in these fields. But you have many of them teaching and researching in many German universities and industries. I have proof of many of them.