He starts feeding the piece through and about halfway thru the cut the piece flies off the router table! He picks up the piece and examines it, must have been that knot that flung it out. Good thing it was the test piece. Starts on the next one and halfway through the piece flies off the table. WTF!
Shuts everything down. Look at the router table wondering which is left and right, start thinking back to the craftsman table he used to have...which way did that arrow point? No. I'm going the right way, it must be the x-grain of the plywood causing the problem. Lets try this again...
Doesn't fly off the table this time, but almost. Newbie examines the bit expecting to find a bent cutter or some other explanation other than user error, nope. Then he looks at mangled piece expecting the wood to say 'sorry won't happen again', no response. Grasping wildly the newbie decides that the router must be spinning backwards... time for a break.
A few minutes sitting on the chair trying to figure out how the polarity was reversed in his router helped the newbie realized he was trying to cut on the back side of the bit.