I refused to hire over 98% of applicants because they showed job desperation. Why do they lack professionalism?

I am a recruiter for small company. My job is to interview and make hiring decisions. Whenever I interview a lot of people show excessive desperation for job. They say stuff like, "just let me put my foot in the door and i will prove it to you how good i am", "i want to work with you because i need a job real bad. i really want to work", or "it is critical for me that i get the chance to work because my life depends on it". I shut out such candidates very swiftly because i don't want desperate and under pressure employees. I want calm, relaxed and confident employee. These applicants act as if world will come to an end if I don't hire. I reject that attitude because it shows negativity on their part. Its simply unprofessional. I interviewed a candidate who was calm, relaxed and smiling throughout. When i asked him, "what if i say a better candidate has been found". He said, "it is a good learning experience for me and I am very pleased that I got the opportunity for being interviewed. There is never a limit for new opportunities in this world". His answer showed no job desperation and i hired him