“Witness statements convict people of crimes all the time.”
It is known that witness statements are unreliable - what they think they saw is often found to not be what happened; perpsective (diferent perspective different view of the same thing and different interpretation of what happened), focus, constant attention, attention to detail, often leads to different “witnesses” not in agreement.
It is also true that witness statements - what persons think they saw - wrongly convict people sometimes.
That is why indpendent and cooborative evidence recorded somehow at the same time is often needed.
Similar but different in some important ways.
Thousands of such witnesses do, in fact, build toward a clear understanding.