One famous episode of the comedy series Seinfeld showed a long line of people anxiously awaiting their turn in a line leading to a soup restaurant. Surprisingly, the store owner was unpleasant and egregiously rude, even refusing to serve one of the Seinfeld cast.
Ironically, this refusal made the soup even more attractive. In other words, human nature is somewhat odd: We want what we cannot have.
This is called a velvet-rope policy: Night clubs become more popular when they are selective and create long artificial lines. All of a sudden, everyone wants to pass the velvet rope to get in.
Scarcity is a powerful motivator and is often used for subtle manipulation in decision making. ‘Only one left in store’ is remarkably effective to entice you to decide now.
To avoid being manipulated by scarcity, I have a very simply rule of thumb when making important decisions. If someone asks me to decide now, the answer is no. There will always be another bus.