I can't hang around here fixing your science all day. I've got documents to write.

I was in lab today and a pair of students were trying to diagnose a circuit. They worked on it for about half an hour before they called me over. They showed me how carefully they'd probed all the components with a multimeter and checked their breadboard connections three times. I listened. I waited patiently. When they finished, I raised an eyebrow.

"I can fix your problem by pushing one button," I said.
"Really?!"

I pressed the power button on their prototyping board unit. The oscilloscope signal flicked from flatline noise into a square wave.

I smiled at them and walked away.