Economy · all games
Sinks and faucets
The two sides of a game economy: faucets add currency and items to the game, and sinks take them back out.
Also called: sources and sinks, faucets and drains, currency sink, currency faucet
A faucet is any source of currency or items: level rewards, daily gifts, ad rewards, purchases. A sink is anything that removes them: upgrade costs, shop prices, entry fees, repair costs. Designers also call these sources and sinks.
The economy stays healthy when the two roughly balance over time. Faucets without enough sinks pile up currency until rewards stop meaning anything. Sinks without enough faucets leave players short, and the game starts to feel like a grind or a wall.
Balance is not a single number. It shifts as players progress, so early faucets are often generous and later sinks grow. Designers watch how much currency players hold and how fast they spend it to see when the balance has drifted.
In mobile games
Mobile economies usually have more than one currency, so each currency has its own faucets and sinks. Upgrade screens are a good place to see sinks directly: the price on each button is currency leaving the economy.
What to watch for
- Inflation. If faucets keep growing and prices do not, every reward feels smaller over time.
- A sink players resent. A cost that feels like a punishment, such as a repair fee after a loss, can cost more goodwill than the currency it removes.
