Why do some men string women along when they know they won’t change?

Why do some men know that they can't give a woman who she needs and wants to string a woman along so the next man can make her happy and give her what she needs if he knows that he can't do it? How much time does a man expect a woman to sit around waiting on a man to change?
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22 h
I met someone last year - he hasn't changed within the 7 months We went on separation and 7 months later we circle back - no significant change with his behavior. He hasn't healed or improved since we last talked and went on break.
Why do some men string women along when they know they won’t change?
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