Simple hair question

Talia
Can someone explain why braids are considered a protective hairstyle? 
And, if white women have braids, is that also considered a protective hairstyle? 
Every time I put my hair in a braid or sometimes two braids I'm able to pull out like 6-7 strands of hairs out of the end of the braid when I'm done. Like it just comes off my head when I braid my hair, maybe from the tension?
So what is protective about a braid I'm very curious cause I'm doing something wrong.