You've probably got, or at least seen, a slide which shows how traditional IT projects build a load of features which don't get used.
It probably looked something like this:
I call the behaviour which causes us to build those low value features "Hoarding". Hoarding is a natural consequence of scarcity. It's also - in a nasty little reenforcing loop - a cause of scarcity.
You can read more about it in my article, "Hoarding: How to Prioritize Features to Clean Up the Clutter", which was published on the Agile Connection* website today.
* If you've not heard of Agile Connection, it's a Techwell Community, bought to us by the folk who publish Better Software magazine and StickyMinds.com. I've been writing for them for years now and they produce great content.