The above is true for two reasons:
1: The baby at birth is recognizable as being perfect,
2: The baby at birth is recognizable as having honed and infallible skills at bullshitting her way out of any circumstance
Few such children are born in our times of Gene Pool Dilution.
Further, Nietas themselves are utterly unaware of their rarity.
Raghav: You're a NIETA?! Oh my god!