This was discussed (sort of) in a thread here last month: https://hawaiifiveo.org/forum/showth...-in-the-Family

But it doesn't give a specific reason why Kam Fong wanted to leave.

If you do a Google search with the question "Why did Kam Fong leave Hawaii Five-O," the first reference is to my own pages and the report of the Mahalo Con in 1996, but it is not specific about this.

Kam's Honolulu Advertiser obituary at http://the.honoluluadvertiser.com/ar.../br/br04p.html says, "He decided to leave Five-O because the scripts had grown 'static' and followed a predictable pattern, he said in a 1977 interview." But I don't know where this interview was originally. Maybe someone can find it with newspapers.com?

His New York Times obit said, "In an interview Mr. Chun said he left ''Hawaii Five-0'' because he felt the scripts were becoming stale." This obit (November 1, 2002) seems to be referring to the Star-Advertiser (Kam died on October 18.) Again, I can't easily find any reference to this interview.

On IMDb, there is a review of this show by "Only Fair" from 20 September 2019 which reads, "[B]y this season, things were getting stale. The scripts were not as good, and the music was less interesting and more."

An obit from November 1, 2002, in the Los Angeles Times said, "Chun played the part for 10 seasons before he tired of it..." This obit is at https://www.latimes.com/archives/la-...gs1-story.html

Another obit at legacy.com says, "Chun decided to leave the show in its 10th season—because he thought it was getting too predictable—Chin Ho’s character was killed while on an undercover mission. 'It was a life that was worth it,' his last words went. 'It was a life that mattered.'"

But the above quotes are not correct. Chin gets tricked by slimy Jimmy Rego into misidentifying where he came from in San Francisco. Rego says, "We made you," and tells Chin that they know he works for Five-O. Rego adds, "Now that ... that was a mistake." As some thugs grab Chin, he tells Rego, "It was worth it. I don't think I have much to lose."

Those are Chin's last words, we don't see him actually getting knocked off.