Because there is no upper limit. Conversion is given for those who talk about so called "sharai haq meher". Sharai is a law of Shara or something fixed by Sahra. Dower must not be less than 10 dirham but there is no upper limit defined. So in Islam, there is no concept of Sharai fixed Haq meher.

Problems sprouted when people started associating dower with divorce. Dower by no means stands for "security". Prompt dower should be paid immediately after Nikah and Deferred is payable at death or dissolution of marriage. It has nothing to do with divorce. Durability of relationship solely lies on trust and mutual love; if its not there, nothing can save the relationship from falling apart.

For boys, it is an obligation. Mostly on the wedding night, husband kinda plea to his wife "Apna haq meher maaf ker do". He has NO RIGHT to make such request.He is bound to pay Prompt dower before touching his wife.

Girls! You need to understand the real meaning of dower. You have the right to demand according to your social position but as Hazrat Muhammad (SAW) said, "The best amount of mahr is that which can be paid easily", make sure the dower remains a gift and must not become a burden for your future husband.

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The Me you have always known, the Me that's a stranger still.