the officers have to make quick assessments in dangerous situations. Dude went at them with a knife in his hand, yelling "shoot me".

It's a job that I don't envy.

On the other hand, there should be some level of effort and training to DE-ESCALATE the situation and PRESERVE life.

Take a step back. Yes, back up literally.

Think.

Make an attempt to talk the man down.

They came out with guns drawn IMMEDIATELY.

This intensified the situation even more from the get-go.

So they end up being justified in using lethal force in a situation that they contributed to the escalation of.