The overwhelming fear of being wrong
She didn't vote because she was afraid her candidate would lose.
He complains that the blog is being published too often and doesn't want to read some of the posts if he's not going to be able to keep up with all of them.
They don't want to buy insurance for their business because the policies are too complicated and they might buy the wrong one.
The family doesn't travel by plane any more because the whole endeavor is filled with apparent pitfalls.
He doesn't want to buy the book because he might not like it. It's better to waste two or three hours doing something he's certainly not going to like instead.
She calls a meeting and then another meeting because it's easier than committing and just saying 'no'. Or 'yes.'
Better not to hire a coach or go to a therapist or even pick a doctor, because you might discover that you've been doing something wrong.
They sell more wine in places where there aren't so many wines to choose from, because complicated selection processes make it easier to buy nothing.
It's far easier to be guy #8. Not your fault.
Almost every marketer I know underestimates how widespread this fear is. It is the lone barrier almost every product and service has to overcome in order to succeed.