Why Did my Female friend lie about her height?

My female friend who’s 31 has always told me that she’s 6 feet tall. Though yesterday when I was at her place yesterday the topic came up and I decided to measure her. She’s actually 5’11.5. Why would she do this? Was she deliberately lying about her height or rounding up? I’m 23 btw. She was measured in her socks without shoes. I’m 5’4 and male.