Normal Term Limits?

I just read that the former Mayor of Honolulu, Frank Fasi, died. He had served as mayor for 22 years!! Known as "Fearless Frank," he once drove a bulldozer to the parking lot next to City Hall and had the parking lot transformed into a park (now named for him). The NYT obituary also says that Mayor Fasi had tried to start a light-rail network (it's about to be built), he bought a private bus company to end a bus strike, and he started community gardens and farmers' markets.

On the one hand, maybe when an elected official becomes known as "Fearless," it's time to think about term limits. On the other hand, citizens kept reelecting him, so they must have approved of his actions. Normal mayors serve 4-year terms but there doesn't seem to be a limit on how many terms they may serve. Should there be a limit?