Not all musicals can sustain a long or profitable run on Broadway. The latest to bite the dust (following “Tuck Everlasting” and “American Psycho”) is “Bright Star,” a sunny, unapologetically sentimental valentine to the postwar American South, innocent romance and over-the-top storytelling, with bluegrass-style songs by Steve Martin and Edie Brickell.

It earned mostly positive reviews when it opened in March, including all-out raves for leading lady Carmen Cusack. And at both performances I’ve attended, it’s proven to be a genuine crowd-pleaser. But despite all that, it’s faltered at the box office and will shutter on Sunday after a short run.

On inspection, it becomes evident that “Bright Star” had virtually no commercial potential and little chance of attracting a sizable audience.

“Bright Star” had no hook on which to build initial buzz. It is a wholly original work (i.e. not based on a pre-existing film, book or pop song catalog), there are no well-known actors in the cast and it is not built around a fresh or newsworthy concept.

By comparison, “Hamilton” got people intrigued from the start (even before the raves began to pile up) thanks to the ingenious notions of having a racially diverse cast portray the Founding Fathers and recasting American history in a hip-hop language.

Martin is, of course, a pop culture icon, but he is not in the cast (although he has made surprise appearances at many performances, strumming a banjo with the band), and he is known as an actor and comedian, not a composer.

“Bright Star” is also so romantic and old-fashioned that it is out of sync with today’s cultural norms. At times, I felt like I was watching a revival of a musical that is not only set in the 1940s but was written back then, too.

Had it opened during a less competitive season (i.e. one not dominated by “Hamilton”), it may have had a decedent shot at winning the Tony Award for Best Musical, which would have certainly given its box office a jolt, the kind that “A Gentleman’s Guide to Love and Murder” enjoyed two years ago.

During recent mornings, I’ve seen long lines around the Cort Theatre, full of theatergoers looking to buy heavily discounted rush tickets. Clearly, word of mouth is spreading, but it also shows that “Bright Star” is the kind of musical that many people would like to see, but not at exorbitant ticket prices. Only a handful of shows can get away with that and succeed financially on Broadway.