Because there are also "female's bicycles". Historically these bikes were designed for women. See the top two answers here: http://bicycles.stackexchange.com/

Because there are also "female's bicycles". Historically these bikes were designed for women. See the top two answers here: http://bicycles.stackexchange.com/questions/13826/what-are-the-differences-between-a-mens-and-womens-bike-frame http://bicycles.stackexchange.com/questions/13826/what-are-t...