If you want something, but it is hard to get, you develop a strong desire for that thing.

If you want something, and it is easy to get, you just please your want immediately.

This relationship between availability and desire applies to all areas of life. In dating being unavailable is what create desire for another person. In fundraising for startups, talking to many investors at once and being unavailable at some times creates fear of missing out and consequentially desire to invest. In marketing, artificial shortage of the latest product drop makes people talk about it and want it more. In a bar not letting everyone in and reducing availability increases the desire to try to get in next time. The list goes on.

This relationship also has a formal theory behind it: the scarcity principle. As humans, we place higher value on the things that are scarce. Inversely, we place a lower value on things that are available in abundance. And this is linked to desire.

You can make use of this correlation between availability and desire. But of course this is no strategy on its own. The first thing you need to succeed at is making something that people really want and love. Then, and only then, you can play with the availability of the thing you are making. Yet, remember:

Unavailability creates desire.

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