The need to be right
I don't think you can underestimate how important it is to most people to be right.
People choose jobs, products, partnerships... just about everything... in many ways because it makes them feel right or at least diminishes the chance that they will be 'caught' being wrong.
The customer is always right. When they're wrong, they're not your customer any more, because it's better to flee than be wrong.
My post on wikipedia really hit a nerve with a large number of readers. In many cases, the feedback I got was that the article in wikipedia might be wrong or vandalized. And if the underlying article is wrong, well, then you would be wrong. And being wrong is... bad.
I like being wrong. Not enough to make a habit of it, but enough to realize that I'm actively testing scenarios. Take a fact of dubious authenticity, riff a scenario around it and see if it feels right. That act of scenario building is a key factor in brainstorming, in creativity and in problem solving. If you need the core fact to be guaranteed right and perfect, you're doomed, because facts like that are in short supply.
Are you setting up your customers to be right and to feel right? Or is the risk of 'wrong' holding them back?
[I know, there's a huge need to have right facts and right practice, particularly in jobs where quality of service is essential. Got that. My point is that we're so good at getting those sort of facts right that maybe, just maybe, we need to spend more time teaching people the other stuff. Short version: if your job can be completely written up in a manual, it's either not a great job or it's going to be done by someone cheaper, sometime soon.]