Mike Tyson on risk management

"Everyone has a plan 'till they get punched in the mouth."
-Mike Tyson 

Isn' this the reason you want to have a risk management strategy? A manager may have an investment plan but markets change and when they do for the negative you get punched in the mouth. So the objective of risk management is to ensure you have a strategy when that punch occurs. You do not plan to have this happen, but those bad events do occur.  One of the simplest ways to deal with the punch is have stop loss orders or limits on any positions. When the punches start coming you are ready with idea of what you are going to do. 

Every strategy should have an exit or protection plan for those times when events go wrong and surprises occur.