Sometimes I mess up my builds or don't think it through properly or assume things or just shit happens. Then wrong materials end up on massive long belts that jam at the end because they cannot be used for production. To flush them belts you have to nuke the belt and replace it because there is a resource jam on the belt deep inside the input port that you cannot remove.
All buildings that produce things must have a "recycle bin mode" where they just bin everything coming into the ports. This way you can flush your belts that contain incorrect materials and un-jam a production factory.
Please we need this.