Football managers are frequently observed jotting notes or conversing with their assistants during games. The majority of these are connected to opponents' strategy as well as their own shortcomings and errors made by their players. Based on the notes, they adjust the approach or make tactical substitutions during halftime. Some even go as far as to say that football is a game of tactics - true enough, but also an art form where much can be achieved through proper preparation. After losses, coaches usually explain why their strategies failed and what needs to be changed for future games. After victories, they often discuss how they could have done things better and what adjustments need to be made for future games. Coaches write down lots of things during games. They may note how many times a player has been substituted by his manager (usually due to lack of fitness), they may observe if any of their opponents' players are likely to cause trouble in certain areas of the field, they may even note if there are any potential threats outside of the area directly in front of their goal. All of this information is used by the coach after the game to help his team improve next time around. Writing down things during games helps coaches think more clearly under pressure. It gives them something else to focus on other than just how the game is going. It also allows them to share their ideas with others so new strategies can be developed together.