Faith, (or belief in the more general sense), is an artifact of survival instincts, (fight or flight instincts), that are millions of years old, (an extension of cognitive functions beyond what our five senses can provide). Belief is an example of what happens when those survival instincts cross with human conscious awareness. As others have mentioned, that crossing leads to cognitive errors, (such as confirmation biases; intellectual laziness; etc.).
Faith is not trust. Trust is based on previous positive experience, (however anecdotal). Faith requires no such experience, let alone empirical evidence. All that is needed is cognitive acceptance of what one considers "real".
The etymological definition of belief is closer to that of "to care, love, desire", etc. Not that any of that is bad, however none of those instincts are based on fact.
d4g