Ask HN: In which areas did you push your comfort zone? How successful were you?

My CV reads like I am a Jack of all trades (and clearly master of none ;-), but I'm currently in a software developer role that I feel very comfortable in, except maybe that there could be more technical challenges.

My current company hired me two years ago with the idea and perspective of making me a team leader, and I am currently going through trainings and other activities that prepare me for an assessment center. Of course there is also a fair amount of proactiveness required.

What I am noticing lately is that I am feeling like I am pushing the boundaries of or even leaving my comfort zone in basically everything related to the team leader position, but I cannot recall ever feeling that way when presented with a technical challenge (which could be an entire master in aerospace engineering or simply diving into an existing Angular codebase).

What's your experience? Have you pushed your comfort zone only within technical areas, or outside? How successful or unsuccessful were you in these areas later on?