Tell your team about the time you messed up worst. It makes it safe for them to be human around you.

People calibrate how much they can admit by what they have heard admitted. If the person in front has apparently never failed, everyone else concludes that failure is unmentionable here and starts hiding the small ones until they are large. A specific story about your own bad decision does more for honesty than any invitation to speak freely.

Tell one real story this week, with the part where you looked bad left in. Do not attach a lesson to the end of it. Watch how quickly somebody tells you something they had been sitting on.