I was eating lunch with my wife today (after replacing the disposal last night), and my wife tells me our dishwasher was putting out an error code. As she picks up her phone to google the code and see what might be wrong with the dishwasher, my mind immediately flashed to the little plastic tab inside the dishwasher drain line port. "The dishwasher isn't draining," I said.
I think she was initially impressed that I could so easily guess what the error code was, but when I told her how I made the right call, I'm sure she was less impressed that the reason for the code was such a simple blunder by the installer.