I get that question a lot about Little Girl's hair. The answer depends on the style.
Took 3 Brady Bunch episodes (our whole family loves old Brady Bunch episodes we get from Netflix).
So about 1 hour and 30 minutes.
And that is just the braiding and beading, it doesn't include the washing and detangling that I did for about 30 minutes prior to the braiding.
If you'd told me 4 years ago there would come a day that I'd spend 2 hours fixing 1 child's hair, I'd have said, "No way! That's crazy!"
But, this is our life now and it's not so crazy, it just is the way it is.
Is it worth it? I mean it's just hair!
In your native culture a little girl's hairstyle may not be a very big deal, but in some cultures, including much of the black culture, hair is very important and how a little girl's hair is fixed represents how well she is cared for. Fixing my daughter's hair in some of the more ethnically-traditional styles is one way to embrace her birth culture. There are a lot of things in life that are going to be different for her growing up in a white family versus growing up in a black family, hair does not have to be one of those things.
And, it's practical! The braids and twists keep my Little Girl's hair much healthier. Her hair dries out very quickly when it is in a "free hair" style and it is much more prone to getting sand, grass, dirt, and debris in it that are hard to get out. Also, while the initial investment of time is a lot, this style will easily last a week with very little maintenance, maybe longer.
My 8 year old white daughter with long, fine, straight hair gets it brushed and fixed a bit each day, sometimes twice a day, and her hair has to be washed nearly every day. So, while she does not get 2 hours put into her hair in one day, she gets 10-15 minutes each day.
And my 4 year old black daughter with her coarse, curly hair, gets 2 hours of maintenance once a week (and some styles do not take that long) and then she only requires about 1 minute each day to add some oil to her part lines!
Another reason it's worth it: She likes it! This style is only the 3rd time I've done beads and I only attempted them after Little Girl and I were reading a book and the girl in the book had braids with beads in the ends and my Little Girl said she wanted her hair to be like that so she could swing it and hear the beads click, click, click together.
And the best reason of all: Little Girl often gets compliments on her hair and people ask her, "Who did your hair?" And she proudly says, "Mommy!" As someone who only got to start being her Mommy when she was 3 years old, hearing her get to boast about something her Mommy did for her makes every minute spent on her hair totally worth it to me!