A Comfort Zone doesn't ask much of you - it's comfortable, familiar and predictable - you know where you stand HOWEVER it's not necessarily the best place for you. This could be a job or a relationship where you are going through the motions and not stretching or moving onto challenges - this is the learning zone - its unknown, risky, anxious and feels scarey - the physiology is anxiety and excitement at the same time.
Growth feels like a risk - but it is a challenge to be embraced with confident and capability.
Unlock your potential - lift those heavy weights - do something exciting and different that codes different proteins in the genes and create new pathways.
It all takes courage and like any muscle the more you exercise it the more you can achieve.
Confidence isn't prior to doing something Courage is. --- what are you waiting for.