Answer:
A lot of things can influence us when we write about ourselves, primarily our own perception of ourselves. Depending on how you feel about yourself as a person, you might write good, neutral, or bad things about yourself, but that depends on your own feelings.
If you want to be a bit more objective, additional things that can influence you are other people's thoughts and opinions about you. This can also affect the way you feel and write about yourself as society can have a huge influence on our self-perception.