I don't watch Hoarders, but I was fascinated by the show's star Matt Paxton talking about what he learned doing the show on the Sklarbro Country podcast.
He said that the one thing that ties all hoarders together is enormous anger. They feel cornered like snakes. The second thing he said is that hoarders are willing to trade their children (letting them go to foster care, which Paxton says is often necessary) if they can keep their garbage.
The third thing he said is that the show is so unpleasant that the staff who work on the show are on the desperate side, on the heels of a failure or other.
Finally, Paxton said he likes doing the show because it helps him work through his own addiction issues (I believe he's an alcoholic).
Will I now watch Hoarders? No. Too disturbing.