When people feel they are in negative situations and those negative situations are outside of their control they become stressed. When under stress people tend to want to either avoid or fight the cause of the stress. When under stress, people often place the blame on other people. Or, they blame the situation. 

When under stress, people do not listen or apprehend as well as they do when they are not under stress. And, their ability to remember may also be impaired by stress. A level of stress can lead to positive change and there may be a little truth in "whatever doesn't kill you makes you stronger".

Regardless, when they are under extreme stress or stress that is sustained over periods of time [maybe hours, maybe days, maybe longer...depends on the person], most people's perceptions become distorted. And, when perceptions are distorted judgement is distorted. It follows that decisions and interactions with other people are also distorted. And distortion brings problems.

Think about these things when you are under stress.

Think about these things when you apply stress on other people.