When trying to build a transport drones depot next to something so that the road cannot be placed, you see floating text "road placement blocked" and you still have the depot in your hand.
https://freeimage.host/i/disappear1.J12C5G
but when using the construction drones, you get the same text, but the construction drone will not take the depot back, and it is gone now.
https://freeimage.host/i/disappear2.J12BJs
