Interesting thread. A man wants a second wife when: 1. His 1st wife is not able to give him children 2. His 1st wife is not a good muslimah 3. His 1st wife is not up to his standards 4. Because it's a common thing in their culture (in some places of the world most of the men have multiple wives) 5. His husabnd doesn't lower his gaze, when watching tv, going on the internet, on the road, at home... his sexual desires are stimulated and his wife who might not look like the next top model is not attended and liked for that reason. 6. Because of his nature, some men are born with extra hormones, for which 1 wife is just not enough! As much i hate the thought of a second wife, may Allah never make my husband even intent on marring another or having a liking for another woman(Ameen), these are the facts and we have to face our fears when the time comes. May Allah give sabr, and istiqamat to all those 1st wives... It must be hard no matter how much they get used to the idea.