The right timing is everything in reinforcing your dog's behavior -- or at least, a key thing for successful learning.

Timing is knowing when to mark. The timing of the clicker ideally is having the click occur at exactly the same instant the target criterion is achieved. Timing is a mechanical skill and requires practice. The trainer (and you) must be able to recognize your dog's behaviors that precede the target behavior in order to anticipate and click at the very moment the target behavior occurs. Your dog will associate whatever behavior was happening at the exact moment of the click sound with being rewarded so that behavior is reinforced to repeat.