Supports are like school teachers
You never know what kinda student you are going to get. Are you going to get one that already knows what to do but just needs some help or are you going to get one that knows nothing and needs complete hand holding? Are you going to get that kid who thinks they know everything and yells at you because they messed up? Are you going to get the one that knows they aren't very good and just rolls with their mistakes? No matter who you get supports are there to help the student but some just don't want it.
Edit: Mister Punches put it nicely. They're overworked, underpaid, and deal with abuse from the people that they serve and protect?
Yeah, that sounds like a support player. We need more love for our supports.