There's a diference between faith and confidence.
I guess you're right, now that I think about it. Confidence is a more appropriate word, once something has succeeded many times over. Faith is more appropriate for something there is no data on, I guess.
Look at the common dictiuonary meaning of faith, and you will find words such as "Confident belief in the truth, value, or trustworthiness of a person, idea, or thing." Faith is not weak or blind. It always has an object.