The American government funded a study to see why the head of a man's penis was larger than the shaft. After 1 year and $180,000, they concluded that the reason that the head was larger than the shaft was to give the man more pleasure during sex.
After the US published the study, the Australians decided to do their own study. After $250,000 and 2 years of research, they concluded that the reason the head was larger than the shaft was to give the woman more pleasure during sex.
The Canadians, unsatisfied with these findings, conducted their own study. After 2 weeks and a cost of around $75.46, plus six cases of beer, they concluded that it was to keep a man's hand from flying off and hitting himself in the forehead.