When you take the Grade 3 guard off the hair clippers to clear some hair build-up, then forget to put it back on and your "do" becomes an inverse Mohawk.
I find having a No.1 avoids this to a degree. have done it a bit too often and given the difference hardly anyone notices... except my wife who almost literally pissed herself laughing when I did it the first time.
When you take the Grade 3 guard off the hair clippers to clear some hair build-up, then forget to put it back on and your "do" becomes an inverse Mohawk.