Parking the Tank
Sometimes if the Tank spawns in a less then ideal place, or the Survivors do something cheap like hide under stairs, Infected players may choose not to waste him.
arking involves sacrificing your turn with the Tank, by placing him in a more favourable position. The AI takes over, and when the Survivors arrive
hopefully what results is a more successful attack.
Left 4 dead (C) Valve
Artwork (C) Daryl Toh Liem Zhan 2009