Often we plan our programs as if the work is in the comfort zone. But the inherent complexity suggests that the work is in the learning zone or even the danger zone.

In the comfort zone, people do the work habitually with little improvements in their capabilities.
In the learning zone, even experienced people struggle, which leads to learning new skills. People need to do the work in small steps and for the primary purpose of learning from each, then incorporate this learning to decide on the next step.