It's because of the way our brain deals with commitment: the more your invest yourself in something, the harder it is to quit. E.G: Put your bad next to a per

It's because of the way our brain deals with commitment: the more your invest yourself in something, the harder it is to quit. E.G: Put your bad next to a person and leave. A thief comes and steal the bag. You have a low change of the person to protect your bag. Do the same, but just ask quickly if the person can keep an eye on the bag. You now have a much higher change that the person will protect it. The risks are the same for the person, and the gains are still zero, but they committed. This have plenty of application in sales, politics, etc. For a very fun ride about this, read "Small Treatise About Manipulation for Honest People ". It explains very well how we trick ourselves into taking weird decisions because of commitments.