The first characteristic of hoarding behavior is excessive acquisition of material possessions. Each hoarder has several pathways of acquisition that are used on a daily basis to continually accumulate items.
Hoarders acquire material possessions for the same reasons that non-OCD people do. But the circumstances of the acquisition are always different. There is always an uncontrollable compulsion to collect more and more stuff. The compulsion is so strong that a hoarder has to literally look away from potential acquisition pathways (such as newsstands, small stores, etc.) to avoid hoarding more stuff.
When a hoarder acquires something, he develops a strong emotional attachment with the new acquisition. This prevents hoarders from throwing out even the smallest, most insignificant items. They would rather sort through their possessions repeatedly than discard stuff. Often, a hoarder would be distraught if they found out that someone threw away even a tiny item from the entire hoard.
What happens when the hoarder himself tries to throw something away?
Well, in the unlikely event that a hoarder does throw something away, he will usually feel a deep sense of regret and will most likely retrieve the discarded object from the trash.
Once a hoarder discovers just how painful it is to throw away material possessions, the hoarder will avoid the activity altogether (because no one likes doing things that cause extreme anxiety). It might sound strange to an ordinary individual, but this is how hoarders think and feel about their possessions.