Here's a taste of what I'm talking about from the aptly-named Tim Sackett Project:

Here are the types of “critical” feedback people can handle:

“You’re doing a good job, would love it if you could get that big project off the ground. That would really help us out!”

Here’s what you really want to say, critically, but can’t:

“You do good at things I tell you to do, and all basic day to day duties of the job. I need more from this position and from you, and I’m willing to help get you there. I need someone who can take a project from scratch and kill it, without me having to babysit the entire thing. You’re not doing that, and that’s what I really need you to do. Are you willing do that?” 

The reality in addition to what Tim outlines above?  If you really wanted a culture of feedback, you'd do a combination of three things:

1.  You'd measure the sensitivity of those you're thinking about hiring through some type of behavioral assessment, because high sensitivity people are divas when it comes to receiving feedback (it's not their fault, it's who they are), and high sensitivity people are also more empathetic to others as well.  That second piece is a positive in many, many ways, but when it comes to giving feedback it means they might delay someone giving feedback if they think there's a chance it's going to hurt the other person.

2. You'd shoot to avoid hiring people who are highest sensitivity, and/or

3. If you hired them, you'd start the on-boarding process by telling them you're trying to build a culture of feedback, and the first time you give them the real deal (Tim's second example in italics above) you're going to break out there assessment and prepare them to not cry on you, or pretend like they're getting ready to jump from the ledge.

Sensitivity.  A positive in many ways when it comes to empathy and a sense of urgency, a blocking characteristic when it comes to trying to get to a culture of direct and honest feedback.

Your job as a manager would be great if it weren't for the people.  That's a joke. OK, it's not.

If you're looking for a team that can take feedback, you better start measuring sensitivity via an assessment as part of your hiring process.