Reacher season 3 is back and as much as I anticipated some solid ass kicking it is really adamant about testing my patience. 

In the most recent episode the majority of it was covering past events for why Reacher really really wants to shoot the baddy in the face. 

However the whole episode is an absolute waste of time because in the three previous ones it was already established that 
1. The baddy killed one of Reachers friends 
2. The baddy is a really bad guy

So by extension I can only assume the writers think that people are a bit thick in the head and need the motive spoonfed to them. 

Now I would like to think this is not me. I don't need to be told explicitly and in details why someone needs to be shot in the face. This is a given in almost every aspect of our lives. 

Someone is a baddy , thus they need to stop being a baddy. It is very simple. 

Generally I don't have issues with flashbacks , or backstories especially in books but I do have a problem with verbosity. 

I think there are simple rules to follow for sharing a backstory during an active story and for me those are :
1. Be poignant 
2. Be brief
3. Do not repeat yourself

For the most part I think books do it well enough, they don't linger on the mundane and even better they give you the history in one clean paragraph and do callbacks to that. 

Although at the same time they do that rather well most books seem to have a big problem with pace in regards to action. 

Taking a whole chapter to describe a single chase or assault is as bad as dedicating every first paragraph reiterating why the hero aught to have some qualms about shooting the baddy in the face. 

Personally unless the backstories finer details have high emotional impact then I think it has no bearing on the story. So unless the how is really engaging then it matters not to the why. 

In most cases the why is as simples as "Because!"