In an interview with EDGE magazine, Shigeru Miyamoto has explained his desire to make games:

I think my starting point was I wanted to write and draw manga. Basically, this hope of mine materialised in game creation. So, to put it very simply, it’s my job. My driving force is that I really love surprising people, creating fun experiences and moments for them, [and] finding ways to help them enjoy themselves.

And I think it’s safe to say he’s been successful in regards to that driving force.