I've talked a bit about mentoring in software development before, and how early on I used to get feedback about me being "intimidating". I never got any concrete feedback regarding that, so I don't know what problems I had specifically. Though I was recently reminded of one particular incident that was a bit cringey for me personally.
This was a bit more than 10 years ago I think. I was usually assigned to mentor new hires, which means fresh graduates who usually needed guidance with a Java (which was our primary programming language at that time) and with our in-house web framework, which could be a bit challenging to work with. That means a lot of my days are spent answering questions or guiding newbies through more complicated tasks.
The incident I remember was with one particular newbie. After they completed a particular task, they asked me to check their work and everything was fine. I don't have the actual wording of what I said but recall making an offhand in-jest remark congratulating them on getting an entire thing done with zero questions and no actual issues. I remember thinking almost immediately afterwards that it was a terrible thing to say since it implies that asking questions might be frowned upon. It's kind of like the difference between just saying "Good job" and "Good job, you didn't screw this one up!"
I might have been overthinking it a bit back then as I don't remember any actual negative reaction to that particular remark. That's not really a good metric though, especially when you're dealing with newbies on their first job. There's power dynamics to consider, so they may not think it appropriate to complain even if something makes them feel bad or uncomfortable.
As a mentor, it's important to actually encourage the mentees to ask questions when things are unclear or to raise conceerns when there are problems. It's an essential communication skill that all developers (maybe arguably all people) should have. And it's not enough to say "Hey, you can ask me questions any time", but you also have to reflect that openness in your actions, your feedback, and your comments.