I have never liked the phrase “Step outside your comfort zone”. Why do that uncomfortable or scary thing? An implication of stepping outside is that I can’t step back inside when I may need to. I have had to commit to something I don’t yet understand.
I prefer to engage in being a learner and take the steps necessary to “expand my comfort zone”. Once expanded it is less likely to shrink in the future. And I can choose the direction to expand it in.