Just use a trash bin, once it's in the trash bin you won't accidentally use it.
You can empty the trash bin if you like but it isn't a mistake not to.
Here is the reality part:
You troubleshoot, replaced the riser(not the usb cable), but you placed the riser beside the rig because it might be the cable or other stuff(thinking the riser is might not be the problem) then you go out the mining area, look at the pool data or remote view, everything is fine and you don't come back to the mining area...you'll forget that you have a defective riser there, trust me you'll forget that you have a defective riser there and will try to use it again, only to be troubled by that defective part in the future.
The key is, if you know something is defective 100% sure, don't be lazy throw that shit right away.