computer bug, n.All

The Computer bug is by being put there by the author.

A Computer bug is often introduced by the wise programmer as a feature

The Computer bug is that you've got a complex system and sometimes it takes a while to get all the components to co-exist peacefully.

A Computer bug is indistinguishable from a feature if it is sufficiently advanced.

A Computer bug is something like tripping going downstairs, and when you reach for the handrail it comes off in your hand.