The attraction to this particular word is the double meaning: one is private the other is commercial. One costs dearly on pyschological, financial and social levels the other makes money and is big investment.
Interesting**
the 1st dictionary definition is the lesser known type of hoarding and the compulsive disorder of hoarding is more of a social construct than a true meaning. It actually states in the dictionary that hoarded information is useful for it's potential future use - but if you collected piles and piles of information that took over your house and you lived surrounded by piles of information surely this is not useful. The assessment of usefulness seems to based on how the information is stored and organised in accessible systems of order. If the information can be accessed with ease by the person hoarding the collection of information then they are a wiz and not a worry.
Hoarding is always concerned with protection and concealing the inside.
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hoarding |ˈhôrdi ng |
a large board in a public place, used to display advertisements; a billboard.
• a temporary board fence erected around a building site.
ORIGIN early 19th cent.: from obsolete hoard in the same sense (probably based on Old French hourd; related to hurdle ) + -ing 1 .
hoard |hôrd|
noun
a stock or store of money or valued objects, typically one that is secret or carefully guarded : he came back to rescue his little hoard of gold.
• an amassed store of useful information or facts, retained for future use : a hoard of secret information about his work.
verb [ trans. ]
amass (money or valued objects) and hide or store away : thousands of antiques hoarded by a compulsive collector.
• accumulate a supply of (something) in a time of scarcity : many of the boat people had hoarded rations.
• reserve in the mind for future use : [as adj. ] ( hoarded) a year's worth of hoarded resentments and grudges.
USAGE Take care not to confuse the same-sounding words hoard and horde. A hoard is ‘a secret stock or store of something’ (: a hoard of treasure), while a horde is a disparaging word for ‘a large group of people’ (: hordes of fans descended on the stage). One way to remember the difference is to think of : stashing your hoard behind the loose board (note the spelling likeness of hoard and board).
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So hoarding as we know it in the personal sense is derivative of a saying and tied to times of scarcity, the great depression, war.... A collector is someone because their collections have a commercial value and a hoarders hoarding is pitied and despised and labelled a disorder and it has no value.