Yerovam was a man who demonstrated impressive management and leadership skills.  His outstanding reputation led him to a high office when Shlomo appointed him as head of the administrative region of Yosef. However, at the point that Milo is built, Yerovam decided to confront Shlomo.  Ahiya HaShiloni's traumatic prophecy, involving the tearing of a new garment, may have come to Yerovam as a result of his confrontation with Shlomo or it might have been the catalyst that caused him to rebel.  

Courtesy of the Virtual Beit Midrash, Yeshivat Har Etzion