Agency is a muscle
Agency is a muscle. I believe it's not an innate trait, but something that someone needs to continuously build reps for, recognizing when they need to practice it.
Agency is really about someone identifying what energizes them and maintaining momentum when energy pulls them forward in a direction. They need to consciously stay in motion towards that direction, even if they're not sure of the details. As long as someone keeps moving, tweaking, tinkering, building, and testing in the right direction, this ultimately helps train that agency muscle.
The opposite also works when there is too much hesitancy, and people let "perfect" become the enemy of good. Then that stopping motion, the opposite of energy, the opposite of momentum, compounds and hardens. It's important to recognize when someone is hardening and to help spark momentum. This is analogous to breaking out of procrastination. To stop procrastinating, someone needs to do a small task in a certain direction and maintain the momentum.
Just recognize that at the end of the day, we're human. We work in energy spikes, and we have our own morale and momentum that we need to maintain.