FYI it’s Full Time _Equivalent_. E.g a new feature may require 1 FTE for 1 week. That doesn’t necessarily mean 1 person 1 week. It may be 2 people 2.5 days each, etc.

Or 9 women to birth a baby in a month.

I don't like being reduced to a quantifiable amount. You end up with crappy managers who have secret multipliers for every employee to try to make their crappy estimates work.

Nothing makes your colleagues dislike you more than it accidentally slipping that your manager sees you as worth 2.5 of them.

Truth. Even saving their bacon, time and again, doesn't help.