Answer:
Hope this helps
Step-by-step explanation:
When historians are trying to learn more or study a topic for a reason of recording they must understand that there are multiple sides to each story varying greatly from eachother. So to understand the topic as a whole you have to use those sources and try to make a understanding. So you bring all the data to view and conjoin it to one piece of understanding. But as time passes the data of that event becomes older and if we learn something new about the event we have to redo the topic making a endless cycle of trial and error.