Successful game design requires focus, which means the designer must understand what types of play best suits their game and make sure that all the game mechanics support it. Planned gameplay allows many different solutions but gives players time to review their options, practice gameplay encourages strategic thinking within fixed maps or rules, and improvised gameplay forces players think on the fly to adapt to random elements. While some games use one category exclusively, most combine them to different degrees and find success in developing systems focused on a primary type of play.