Farmville got lots of users from Facebook
Farmville was introduced as a Facebook game. Farmville took advantage of Facebook’s growth and got millions of users as a result of utilizing the social network’s graph.
Facebook game requests were still new
When Farmville was released Facebook game requests were still new and people weren’t blocking them yet. This led to further popularity of the game.
People were forced to come back
Farmville used a time based mechanism , which was a relatively new concept, to bring people back to the game. A gamer had to come back often to save his crops.
Users post their accomplishments
The fact that many users post their accomplishments on the wall has introduced so many new people to the game fast.
A sense of social obligation
According to businessinsider a sense of social obligation motivates people to play as a person can hardly succeed in the game if his friends let him down. A person feels obliged to help his friends back because they helped him with gifts.
People invest effort and time
Some people don’t abandon farmville as a result of believing that they invested a great amount of effort and time growing their crops. (See Why was Maplestory so popular?)
The game was designed to go viral
Farmville was desinged to go viral as it depends greatly on requesting help from friends.
Copied a successful game
Zynga copied a successful game , Farmtown, but improved it by focusing on the social part and so it became more successful than the game it copied.
Competition wasn’t high
Farmville launched when Facebook games were still a new idea. The low competition helped early games rise fast.
People who bought virtual goods returned back
The ones who got frustrated to the extent that they bought free goods were forced to come back. People didn’t want to make an investment then abandon the game.
People are already on Facebook
When a person gets a game notification from farmville when he is already on Facebook all what takes him to come back to the game is a click. (See Why is Cut the Rope so Popular?)
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