英语智力测试初二A little girl lives with her family on the tenth floor of a building

英语智力测试初二A little girl lives with her family on the tenth floor of a building
A little girl lives with her family on the tenth floor of a building .Every morning she goes down in the life.Then she goes to school.She comes back from school in the afternoon and she gets into the lift on the ground floor .She goes up in the lift but she stops at the eighth floor .She gets out and walks up to the tenth floor .Why does she walk from the eighth floor?