My first lesson in covering losing short sale trades came after shorting Harley Davidson into earnings numbers.  I had done my homework, and knew they were likely to under report revenue during the late 1990's.  The stock was around $50 per share at the time and I figured I had an easy flip into earnings.  They released numbers shy of what the street was looking for and management guided earning higher for the next quarter and the stock exploded higher.  My boss came by my desk and said that I was stupid for shorting something people were willing to tattoo on their bodies.  Looks like nothing has changed.