Actually it was the test groups. Jar jar was actually slated to be a with (no kidding). Watch when he addresses the senate and waves his hand like doing the mind control motion. The test group found that 1 jar jar did not fit the mold of the sixth enough and was out of place. 2. The minority group bashed that using him as a negative role model make all the great things minorities of that type do look negative. Many articles on it including Lucas avoiding discussing it after opening the can of worms in an interview.
I personally like jar jar. Like him a heck lot more than Mace " I am the boss but why is my hand missing" Windu
