Alexios was for many years under the strong influence of an eminence grise, his mother Anna Dalassene, a wise and immensely able politician whom, in a uniquely irregular fashion, he had crowned as Augusta instead of the rightful claimant to the title, his wife Irene Doukaina. Anna Dalassene's ability to help him seize power and control the aristocracy, as well as her ability to understand and resolve dilemmas, assured Alexius that her mother was a capable counsel and managing partner by his side, and a sane and trusted regent in his absence.
Alexios had been greatly influenced by his mother, Anna Dalassene, who was a powerful political figure who helped him gain power and control over the aristocracy.  Anna's ability to understand and resolve problems made Alexius confident that she was a capable advisor and business partner, and a trustworthy regent when he was away.