I'm a big proponent of "I don't know" being a safe phrase on my team. I would much rather hear "IDK" than hear (and see) someone grasping for an answer.
That being said, it helps nubies to empathize. Let them know this is very common. When new devs start working, I think they are used to being the smartest person in the room their whole lives. Suddenly, everyone is just like that! It's a shocker for them. Eventually the shock wears off and they become more comfortable being vulnerable.
Wish I had a boatload of humility to pass around. We could save a lot of time getting through this issue!
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