There are many types of games to play these days; you can choose to play one that can be easily played on your own, but there are as well others that can be played in group of two or more players.
While there is nothing wrong with playing a game on your own (especially the ones that are mostly related to creativity and testing your level of focusing and intelligence), the majority of players will have more fun when playing the MPG format of games. It is in the nature of human being to feel themselves more challenged when playing a game as part of a competition. Not to mention that the volume of fun that players can get is considerably increased with MPG types of games.