eHarmony is run by a evangelical Christian (who's friends with James Dobson, the Focus on the Family guy). As such, they don't do matches for LGBTQ people. (I guess I wasn't heterosexual enough for them, even though I identify as straight.) Other things they look for include past marriages, current mental health issues, and (I think) your relationship to your own parents. I think the website says that 1 out of 5 people aren't able to be matched, so it clearly happens to a lot of people.

Wait, you answered "Nero" for something? That might explain the rejection! ;)