"Hoarding is not the same as collecting. In general, collectors have a sense of pride about their possessions and they experience joy in displaying and talking about them. They usually keep their collection organized, feel satisfaction when adding to it, and budget their time and money.

 

Those who hoard usually experience embarrassment about their possessions and feel uncomfortable when others see them. They have clutter, often at the expense of livable space, feel sad or ashamed after acquiring additional items, and they are often in debt."

(http://www.adaa.org/understanding-anxiety/obsessive-compulsive-disorder-ocd/hoarding-basics)