The scalability of a service describes how expensive it is to operate as it grows. The more users access the service, the more expensive it becomes—but how much more expensive? The answer to that question is the service’s scalability. As we design services, we want them to be as scalable as possible so that their growth results in higher revenue out of proportion with the increase in expenses.
It is possible—in fact, quite easy—to design the opposite kind of service, where growth results in greater expense growth than revenue, and which therefore “hits a wall” and can no longer profitably grow.
How do we design services that scale?
One day a young angel, only three and a half billion years old, very naive, with limited experience of the wide universe and eager for more, was called over by one of her elder brothers. “I have a special mission for you,” he said. “It is said that Life has appeared somewhere in the universe, in accordance with the purpose and timing of the Almighty. It is your task to seek out this Life, and when you find it, tell us so that we may visit the planet to nurture and guide it.”
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