Enemy commanders had to be careful to eliminate the GLA Hole each time they destroyed a GLA structure, or the hard work of their troops would be undone. However, Holes are rather easily destroyed, not delaying a thorough attacker overmuch. The GLA Hole also has an unused animation of the door opening, so the worker can go through and rebuild the building. Due to a programming error, this animation never actually plays, therefore the worker goes through the closed door.