Taking side with management
Have in mind that siding with management is extremely unpopular among coworkers. Once happened, it is highly unlikely that you will regain „good buddy” status with them. Think first whether it's really worth doing it. Don’t assume gratefulness or any compensation from your boss. Do it only if your boss’ boss acknowledges and appreciates your behavior. Cover yourself by referring to any company policy, such as employee suggestion scheme or quality assurance. Never take side with management if you are a shop steward or any other kind of elected employee representative.