Well, that explains it

One of the more interesting things about reading about hoarding is finding actual explanations of why hoarders do the nonsensical things that they do. I grew up as the daughter of a mother who saved milk jug caps and boxes of miscellaneous paper. I am the granddaughter of a man who lived in a house stacked with so many newspapers that he had small aisles to walk through, plus a backyard filled with oil drums left over from the oil shortage in the 70's. This meant that, even as a child, I spent a lot of time being completely mystified by what went on in my family. Why was it so hard for them to throw out things that were clearly complete garbage?

Turns out, among other things (and this will surprise no one who is a hoarder's child), hoarders find decision making much more difficult that the average person. This New York Times article discusses a study by David F. Tolin, a professor of psychiatry at Yale and director of the anxiety disorders center at the Institute of Living in Hartford. When the brains of hoarders were scanned while they tried to make irreversible decisions about what to discard, the part of the brain involved in decision-making lit up like a Christmas tree. They showed clear signs of stress and difficulty making choices; non-hoarders showed no such effect.

In practical terms, this means that when I pick up a piece of junk mail, I think, "Piece of junk mail. Recycle it. Done!" When my mother picks up a piece of junk mail, I'm pretty sure that the thought process goes something like, "This is a piece of information that could be valuable someday. Maybe I should recycle it? No, I might need it later. Maybe I should put it in this towering pile of papers on the couch? No, maybe that's not a good place for it. Maybe I should put it into my incredibly overly-detailed filing system? No, if I can't see it, I might forget about it. Maybe I should, um...." At this point, the piece of junk mail is clearly not going anywhere, so it's put somewhere to be dealt with later. Multiply this process by one bajillion pieces of detritus filling the house and you'll begin to understand, at least partially, why the decision to discard something is never really made.