I myself don't fully understand all of the "new genders".

To me, your gender is related to your genitals, at birth, if you have a vagina they'll say "it's a girl" if you have a penis they will say "it's a boy".

Now I don't want people to shout at me for "being ignorant", I just want it explained because I don't understand it.

I understand that some people are born in the wrong bodies and wish to transition to the other gender, which makes then "trans-gender".

But that doesn't make "transgender" their gender, it means they are not still the gender they were assigned at birth.

What I don't understand is why some people that wish to transition, whether it's FTM or MTF don't want to have the gender reassignment surgery?

For example: they will be living as a woman, with breasts and take hormones and testosterone blockers, but still have a penis.

I understand that not everyone can afford it (I'm not talking about those poeple).

And I understand it isn't done in an instant, but why, if you want to be the other gender, would you choose to keep the genitals of the gender you no longer wish to be?