Only three left in stock

There were four this morning. There will be four tomorrow. Scarcity is the oldest trick in the shop, and it still works on you.

Only 3 left in stock. Seven people are looking at this hotel. Offer ends at midnight.

You know these are tactics. You have known for years. They still work, and it is worth understanding why, because knowing the name of a trick and being immune to it are different things.

Scarcity does two things at once. It raises the value of the object, since things other people want feel more worth wanting. And it raises the cost of waiting, because now the option might not be there tomorrow. Both push in the same direction, and both bypass the question of whether you wanted the thing in the first place.

The tell is that the pressure comes from the seller’s timeline, not yours. You did not wake up needing to decide by midnight. Somebody chose midnight for you.

A simple habit works. When you feel the pull, ask what happens if it is gone. Most of the time the honest answer is that you will buy it somewhere else, or buy something similar, or discover you did not need it. Very occasionally it is a real loss. The point is to check, because the message is designed so that you do not.

In healthcare this one has teeth. “Limited places on the trial.” “Only a few appointments this month.” Some of it is true. Enough of it is not that the question is always worth asking.