The thing about stepping out of your comfort zone is that you need to be safe to do so.

I used to have some real issues with the phrase 'you don't grow in your comfort zone', because I grew more effectively when I was in (what I thought was) my comfort zone. It turns out it wasn't comfort, it was safety, and I had linked the two.

When you grow up not being used to safety, whether that be emotional, physical, financial, etc, a feeling of safety is noticeable, and feels like comfort. So I was growing in what I thought was my comfort zone, but was actually me being safe, because you can't grow in comfort, but you definitely can't grow without safety.