The following thoughts are taken from Making Metadata: The Case of MusicBrainz, a research study written by Jess Hemerly.
"Obsessive-compulsive disorder is a colloquialism within the MusicBrainz community, and many of the interview subjects referred to themselves and other editors as “OCD,” “obsessive compulsive,” or expressed similar sentiment.
"These users are not clinically diagnosed as OCD ... but they use it as a way to explain their willingness to spend time agonizing over details that those outside the community would see as meaningless. They value neatness and order for practical reasons, but shrug it off as a personality trait that the editors share in common.
"The OCD phenomenon as motivation is both extrinsic and intrinsic in that editors feel compelled to correct the data—a kind of compulsion-based motivation—and extrinsic in that this extreme attention to detail carries over to their own music collections. Many editors described very regimented processes by which they add new music to their collection, and getting the data right in MusicBrainz is a part of that tagging process. It makes it a better information resource, thus satisfying their information need."