It's a combination of conservatism and patriarchy at the religious leadership level. Originally, the rules were clear for either gender: If a Zoroastrian married outside the faith, their child was not Zoroastrian anymore. However, certain influential families were able to gain acceptance for children where the father was Zoroastrian and the mother was not. The priests, however, refused to accept the converse, even though most children learn to practice their faith from their mothers.

This issue has bifurcated the community between the conservatives who agree with the priests, and liberals who support Zoroastrians marrying outside the community. Zoroastrians are largely Westernized, ergo women are educated, have careers and choose their own spouses, and women have long since complained that this system is unfair to them. Some priests, particularly in North America, UK and Australia, are espousing the liberal philosophy and will conduct the initiation ceremony for any child as long as one spouse is Zoroastrian.

In addition, there are also those who feel the situation is dire enough such that conversions should be allowed again.