Why is it important that a historian considers people's perspective and biases; evidence; trustworthiness before they formulate their historical perspective?

It's important because they do not want to teach disinformation, misinformation, or just plain out lies. Here's an example, let's say a historian was asking a co.vid denier if co.vid is real, and if that historian didn't know any better then they will write that down and boom history.

Explanation:

This should be common sense not just for historians.

hi how are you doing today? if you ever need just tell me

the pogroms became known as kristallnacht, the "night of shattered glass," for the shattered glass from the store windows that littered the streets. the morning after the pogroms 30,000 german jewish men were arrested for the "crime" of being jewish and sent to concentration camps, where hundreds of them perished.