Many fiber artists acquire a stash of yarn by purchasing yarn they find attractive, even though they don't have a particular project in mind. This yarn is then stashed somewhere in their home until they find a project to use it for, similarly to how squirrels stash away nuts for the winter.
At Yarned and Dangerous, many regular customers have acquired impressive stashes of yarn because the locally hand dyed yarns are so unique that they simply cannot pass them up.  They know they are one of a kind!