I think that some are great people, some are good people, some are decent people, some are not-so-good people, and some are terrible people. And all the other variations in between. They're people.

Different people mesh with different people. Some they will mesh with better than others. That is normal.

Some will be great people and good at their jobs. Others might be great people and not so good at their jobs. Some might be terrible people but good at their job, and others might be terrible people and horrible at their jobs.

Just like every other job in the world. There is a huge mix of people.

How do they select who gets good treatment or not?

I think that the true value of a person is based upon how other people view them. If they are cared about by someone, then they are valuable to that person. To another person who does not care about them, then they are not valuable. To themselves they are hopefully valuable. I do not think that there is any criteria for what makes someone valuable.