NCIS seemed like one of those franchises. You know? One that would be able to set a spinoff in any setting, with any cast of characters, and be to secure a decade long run on CBS. Well, turns out that is not the case, and NCIS: Hawai'i was the proof. The show was canceled after only three seasons.
But why? Fans seemed to be over the moon for the cast, and Hawai'i even made the tactical move of bringing in a beloved NCIS: Los Angeles character to boost its ties to the rest of the franchise? Well, the way CBS Entertainment President Amy Reisenbach put it, the spinoff was not profitable enough following the Hollywood strikes.
NCIS: Hawai'i was canceled due to dwindling ratings

"Everything came back [from the Hollywood strikes] really strong, but ultimately we have to look at the cohesiveness of the schedule flow," Reisenbach asserted. "We have to evaluate the financials and the performance overall, and we make tough decisions.”
The CBS Entertainment President admitted that NCIS: Hawai'i was one of the shows that brought about a "tough" conversation with showrunners. The ratings for the third season bear out what the network noted. Hawai'i had 5.6 million average viewers during the season premiere, but by the middle of the season, they show was pulling in 4.8 million average viewers. Not an ideal number.
It didn't help that the spinoff shot on location in Hawai'i, which boosted the budget on a show that was already struggling to amass the ratings of its peers/predecessors. CBS President George Cheeks did speak on the possibility of the show getting picked up for season 4 by Paramount Plus, but he did not mince words. He told Variety that "budgets are challenged," and the sizable Hawai'i budget is not the short of thing that the streaming platform supports.
CBS boss asserted show will not be revived

But wait, you might say. CBS has decided to resurrect SWAT twice, after canceling it twice, so maybe there's hope that there will be a reversal that plays to the spinoff's benefit? Well, again, we will not be holding our breath on this one. Amy Reisenbach was asked whether there was a chance Hawai'i could get similar consideration, and she stated, plainly, no.
Besides, CBS has been cleaning house as of late. Not only did the network cancel SWAT a third time, but it canceled two of the FBI spinoffs as well, Most Wanted and International. The network is going in the direction of new spinoffs, for both NCIS and FBI, which means there will be little to no room for these spinoffs that were cut off early.