I would love to read a detailed paper on why 4H was started because it seems like it was a bit of a back door approach to win farmers over to advanced technology. According to their own website, university researchers met resistance with adult farmers who were not accepting some of their new ideas (or rather agricultural discoveries) they were trying to promote. So they started clubs to work with the younger generation, who were more open to the "new ways", hoping they would convince the adults to give them a try.
However, another website, that has a more extensive history published, worded it a bit differently...
The 4-H Pledge
Photo Credit: jimmywayne