Continuity mistake: Aboard the boat, when Danno draws his gun, both his suit and his tie change colors and patterns completely between takes.
A Thousand Pardons -- You're Dead! - S2-E1
Factual error: At the end, Simms shoots at McGarrett and is instantly riddled with bullets from the 8 or 9 cops who shoot back. Yet, when McGarrett walks over to the body, there are no holes - and no blood - marring Simms' pristine uniform. (00:48:00)
Continuity mistake: At the end, Krenter is shot during the final gun battle on the beach. Between takes, his body and the deflated rubber raft that was also on the sand both disappear. (00:48:00)
Continuity mistake: Although the plane making an emergency landing is repeatedly referred to as a jet, the aircraft we see in the air (and later landing) is a prop job. (00:03:00)
Plot hole: Nadira hides from the bad guy behind a screen - with her feet in plain view. Then, after capturing her, the bad guy inexplicably lets her go, even though her knowledge poses a danger to him. Given that he's killed without a qualm before, this makes no sense at all.
Continuity mistake: 12-17 "A Bird in Hand": We see Angie take photos of mobster Del Vecchi with a 35mm camera. But later on, she develops the same photos and says she took them with a 110 camera hidden in her purse. She's a professional photographer and would certainly know the difference between 35mm and 110 film.
Continuity mistake: The bad guys are driving a dark green '62 Cadillac - with fins. After Five-O's sharp shooters fire at it, the Caddy hits a concrete wall. In the next shot of the wreck, the green '62 has turned into a black '64 - without fins. (00:42:45 - 00:44:35)
Twenty-Four Karat Kill - S1-E8
Continuity mistake: McGarrett gets out of his car wearing a gray suit, and walks into Dennisen's office wearing a blue one. (00:20:15)
Highest Castle, Deepest Grave - S4-E1
Revealing mistake: Stock footage turns the doctor's black 1970 Lincoln Continental into a 1950s model when it goes over the cliff, crashes and burns. (00:15:50)
Here Today, Gone Tonight - S5-E17
Continuity mistake: Danno boards the helicopter without his briefcase, but arrives to conduct the interview carrying the case and tape recorder. He takes the copter back home again with nothing in hand, getting into his car empty handed as well. But he enters McGarrett's office carrying the briefcase again.
Revealing mistake: When McGarrett and the modern-day posse find Frank's euthanized horse, the "dead" animal is quite visibly (and vigorously) breathing. (00:45:20)
Air Cargo -- Dial for Murder - S4-E7
Visible crew/equipment: In the office, when McGarrett hands Chin Ho the murdered cop's notebook, the microphone shadow can be seen moving across the set wall at the upper left of the screen. (00:14:15)
Continuity mistake: At the airport security checkpoint, Sam drapes a garment bag over the counter, but leaves after the inspection without taking it. Next shot, though, it disappears. (00:44:30)
Factual error: 8-12 "Honor is an Unmarked Grave": Marshall has been in Hawaii for only 3 weeks, yet he has his cat, which he brought along, living with him. Hawaii requires a 4-month quarantine on all pets brought in from the mainland. Marshall's kitty should still be in lock-up.
You Don't Have To Kill To Get Rich -- But It Helps. - S5-E3
Revealing mistake: When the shot pans to its feet, the dead body floating in the water can be seen to wiggle its toes.
No Bottles...No Cans...No People - S4-E2
Factual error: Johnny makes two direct-dial calls from his car phone and is instantly connected - something not yet possible in 1971. His calls would have to go through a mobile operator before connecting. (00:32:30)
Revealing mistake: 8-5 "Death's Name is Sam": The plane hit by the missile is a little too obviously a still photo with the explosion superimposed over it.
...And I Want Some Candy and a Gun That Shoots - S4-E6
Continuity mistake: Danno boards the helicopter wearing a brown suit, but arrives wearing a Hawaiian shirt. When he gets out of the aircraft a few shots later, though, he's back in the brown suit, with no time to have changed.
The Grandstand Play (1) - S3-E23
Continuity mistake: The monogrammed handkerchief has cursive initials the first two times we see it. But when Lon gives it to McGarrett, the initials are in block letters.
Visible crew/equipment: When the bad guys pull up to the loading dock warehouse, the door of their shiny black sedan reflects several large round studio lights. (00:32:15)
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.