No Battle Is The Same As The Previous One

In the history of military warfare, hundreds (if not thousands) of battles have been lost by superior armies that have failed to adapt their strategy to the new battle. In other words, they have continued to fight the "last war" where the enemy has learned from its losses, adapted to the conditions, adopted new tactics, practiced those new tactics and implemented the same in the next battle. 

As player, it is important to never ever "rest on your laurels". You must always seek to improve and develop new weapons and new tactics because you can bet your bottom dollar that the opponent is doing exactly the same thing after hit initial defeats. When coaches tell you that you must learn from your losses, the misconception is that you must learn ONLY from your losses. This is not the case; you must learn from your wins as well. Always figure out what worked for (along with what didn't) and determine ways for the opponent to breach your defenses (or break down your weapons) so that you can anticipate the attack during the next battle. For example, if you beat your opponent with a great inside-out forehand (I use this example a lot since it seems to be the meat-and-potatoes play for most players), make sure that you also practice hitting against a slice or heavy/hard down-the-line backhand from the opponent. Also, make sure that you are comfortable coming in or hitting passing shots off your backhand since the opponent may practice a new "play" between tournaments and seek to use it against you. 

Too often, players develop the mentality that because you've beaten an opponent in the past you will do so again in the future. WRONG! Every match, like every battle, is different. Not only will your opponent play differently but, often, the conditions will be completely different as well. Where you may have beaten him on a slow court, now you have to face him on a fast court. It may have been hot before - favoring a bigger hitter - but now it's colder (or windy) - making it difficult to generate pace. A soldier who takes the battle for granted and who is not ready for the element of surprise is a dead soldier. Although the stakes are dramatically lower when it comes to sports, the same principle applies. Expect the unexpected and you will find yourself victorious over and over again.