... And They Painted Daisies On His Coffin - S1-E7
Continuity mistake: When McGarrett arrests Big Chicken at the end of the episode, he twists Chicken's right arm up behind his back, but then in the next shot, Chicken's arm is up above his head on the door in front of him. (00:49:10)
Not That Much Different - S1-E23
Continuity mistake: When Steve is questioning Lannie Devereaux, his arms change position several times on the back of his chair, without him actually moving. (00:24:15)
Answer: He was fired. He never really appreciated his character. He felt Kono was portrayed as a big dumb Hawaiian and that the stereotype was racist. He also felt underutilized. He was fired after a heated argument with the show's publicist regarding his character. It seems there's not much details given regarding the incident or the firing, so it's seems possible he upset the show's producers as well.
Bishop73
No he said something derogatory about one of the Jewish producers that's why he was fired.