It seems amazing now but it was based on the idea that mobile phones would not appear in anything like the numbers they have. The idea that in places like Africa where getting a phone took 10 years that they would have hundreds of millions of cell phones would have been seen as pretty crazy in 1989.
McKinsey made a prediction that there would be about 900K mobiles sold in the US in 2000. They were off by 10s of millions or thousands of percent...
This link says it was made in the early 1980s but the prediction was later than that. http://www.samizdata.net/2007/06/fun-with-statis/
It seems amazing now but it was based on the idea that mobile phones would not appear in anything like the numbers they have. The idea that in places like Africa where getting a phone took 10 years that they would have hundreds of millions of cell phones would have been seen as pretty crazy in 1989.