I ordered a fishing hut to be built and went on my way. After a while I realized I had not gotten the notification that it had been completed. When I checked on the construction, it was partially done with a red exclamation point over it. It was my understanding that once you had the necessary materials, a building could be built. Is there something else that can go wrong to halt construction of a business?

Yes, if there are not enoug workers in the building (as indicated by the red exclamation), they wont bother starting to build it

(i do realize that this thread is awfully old, but maybe someone else reads this as well)

ya, ur gonna need 30 settlers per Building you Build

AND 120 in living space if its ur own city.