Question

What does coin flipping have to do with social neuroscience?

Answer 1

In one's life 20% major decisions make 80% one's life that need time to decide. 80% of minor decisions contribute to 20% of life which doesn't need much time to think but research shows that people are more confused with minor decisions and spend more time thinking and worrying about it. So flipping a coin resolves this conflict and satisfies our mind.

Flipping a coin means, a decision is taken quickly because it's either this or that. It thus saves lots of worrying or confused time.
Choice closure is a term used by psychologists that suggests that when one flips a coin to decide there are no alternatives, it's just one final thing to go with. More the choice more the trouble.
Minimizes regret because we leave the choice or decision in the hands of fate or chance. So we have nothing to regret about.

So flip a coin for a small decision and be happy.