There are innumerable people who never get in touch with Dhamma. They might even be born in a place where the Dhamma is being preached, but they will have no opportunity to hear it. There are many more people who will not be searching for the Dhamma, because they're still searching for the escape route in the human endeavour, looking in the wrong direction. Having come to the conclusion that the world will not provide real happiness, then one also has to have the good kamma to be able to listen to true Dhamma. If these conditions arise, then faith results.
Faith has to be based on trust and confidence.
If these are lacking, the path will not open. One becomes trusting like a child holding the hand of a grown-up when crossing the street. The child believes that the grown-up will be watching out for traffic so that no accident will happen. The small child doesn't have the capacity to gauge when it's safe to cross, but it trusts someone with greater experience. We are like children compared to the Buddha.