What are the reasons a woman would reject a marriage proposal?

Most of the times, she's going to say yes to her boyfriend's proposal. This benefits us more than living together. However, a couple marriage proposals have been rejected too. Few times but yes it does happens.

But seriously what are reasons for a woman to decline a marriage proposal (something that benefits her)?

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+1 y
Right there she's rejecting something that benefits her.
What are the reasons a woman would reject a marriage proposal?
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