There are a lot of different things that fall under what we call "Gender"... your body, your presentation, who you identify with, who you're attracted to, how others relate to you. Each one of these is a spectrum rather than a black-and-white choice. Where you are on the spectrum can change. So some people might not want to fully adopt a new gender identity because they're not comfortable with all aspects of that identity, at least not all the time. Being forced to identify as cisgender or transgender can be like being forced to identify yourself as a tall person or a short person when you're really medium height.
