Unsuccessful Job Interview

Recently had a job interview for a nursing management position at a small facility. I have a lot of clinical experience and management experience in a much larger facility. I have interviewed and hired nurses in my career. I believe I interviewed well with directors and physicians and staff. Was dressed appropriately, researched the facility and thought it was a successful interview. I was told that I wouldn't be offered the job, because i did not seem interested; it didn't seem that I really wanted the job or was ready to make a move from my current job.
I am confused. What is that really about?