Strategy for this next engagement combines geographic requirements with characteristics of the city. Ammoron had not valued Antiparah highly, so the Lamanites gave it up without a fight. Cumeni, a more important site, was defended by a strong army. It is interesting that Helaman describes Manti as the next objective after Cumeni because Zeezrom lies between Cumeni and Manti.
The fact that the Nephites could skip Zeezrom and go directly to Manti suggests that Zeezrom was not defended by an army significant enough to require its reduction. Manti, however, would have been a much more important city, mentioned frequently in the book of Alma.
Helaman reports that the ruse by which they recaptured Cumeni did not work for Manti, its defenders having learned quickly from Cumeni’s fate.