I had wondered why those computer pictures that appear while the computer is on idle mode or starting have none from Nigeria. We have beautiful places like the Manbila plateau, the oghe hot springs, obudu cattle ranch, yankari games Reserve etc. Why are they not getting pictures from these places despite the huge Nigerian market that give them such patronage ?

because is all about good photography not about the place.
If you can capture even your bedroom with the best lightings, perfect timing some one will see it and use it.
Most pictures you see there, the photographers submitted somewhere and it was chosen.