Hindus and Sikhs: Would you marry a Muslim? Watch
Muslims have a bad reputation for conversion, tbf.
Islam is an abrahamic religion (with Judaism and Christianity), and share more beliefs with them than the Hindu Branch (Sikhism, Jainism, Buddhism etc).
If you were anywhere near religious, having kids would be a problem, again because of the rigidity of the prayer system in Islam, as well as different beliefs on the two certain things: death, and (if you are theistic) God.
Hindus have many Gods, and believe in the soul being reincarnated, whilst Islam believes in an afterlife with your physical form (if i'm not mistaken)
TL;DR- Bad blood, cultural values and religious beliefs are different