Farmville is a valuable tool for understanding your weakness in the face of loss. The sunk cost fallacy is the engine which keeps Farmville running, and the developers behind Farmville know this.
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Within a few minutes, you’ve done everything which can be done on your first garden, but there are hints all over the screen portending a fully functioning Texas-ranch-sized megafarm, should you plant your seeds well. Once you learn you must wait at least an hour or so to continue, you start clicking around and find you have coins and cash which can be spent on trees, plants, seeds, an impressive bestiary of jaunty fantastical creatures and a bevy of clothes, devices, buildings and props. You have just enough currency when the game starts to buy a caramel apple tree or some honeybees, but the nice stuff like pink tractors and magic waterfalls, will have to wait until you’ve played the game a while. If you stay vigilant, checking back throughout the day to see how close your strawberries are to being ripe or if a wandering animal has visited your feed trough, you can earn more virtual currency and advance in levels and unlock more stuff. You’ll need to plant and plow and harvest to advance, most of which is also an investment in something which must be harvested…later.

This is the powerful force behind Farmville. Playing Farmville is a commitment to a virtual life form. Your neglect has consequences. If you don’t return, your investments die and you will feel like you wasted your time, money and effort. You must return, sometimes days later, to reap the reward of the time and virtual money you are spending now. If you don’t, not only do you not get rewarded, you lose your investments.