I used to work in HR, so this is what I saw the recruiter doing. She would get all excited about a candidate, then the department head would either not be interested, or found someone else and neglected to tell the recruiter. Typically, they ask for a second interview because at that moment they are excited about you, but then conditions change. Either someone who is connected to the company in some way (friend or family member of someone who works there, or a vendor) becomes interested in the position and they get it because they know someone. Or, something in your background check didn't look good. Remember, that if you think you have been discriminated against, you have the right to file a complaint at your states board of labor.