Coaching your dog to stop biting does not need to occur after a biting incident, it would need to start from when your dog is a puppy. The earlier training begins the less probable it is that a bite will occur. But, even dogs that are loving and sweet may one day have a biting incident. Training your dog early will help to prevent it, but it will never give a 100% guarantee that there will never be a biting incident.
Aggressive dog behavior doesn't happen out of the blue. Because we don't understand dog language though, we may think that dog aggression is unreasonable. It is important to understand that the first step to solving problem behavior among dogs is to first understand the reasons behind them.