Actually Bush told him to leave and gave him a countdown. Saddam wasn't too thrilled with being told to leave and I think that is what made Saddam stay.
My recollection was that he had built a compound in Libya for he, his family and associates - more affectionately known in Libya as “Saddam City.” The story was that when the invasion started he would go into exile there. He also has billions tucked away somewhere, possibly there.
But, he became convinced that with the recent American failures in Vietnam and Samalia he could go to ground and come out the winner. His advisors may have convinced him they could line up the Democrats in Congress to work in his behalf.