Purpose is not meaning. We create a purpose that should be meaningful, but meaning has to be discovered, it cannot be created. We discover meaning through values, guided by conscience. Those values are creative, experiential and attitudinal.
We are often told about the importance of setting goals, but never why we should set them? In to-days Irish Times it gets close, but here is the real benefit. Goals create reasons and we care about reasons more so than causes. Reason and cause are not the same. The reasons that striving for a goal create are often those conditions that cannot be achieved directly. Conditions of satisfaction, fulfillment, happiness, pleasure and accomplishment. Try targeting them directly some time and see how easily they evaporate. They have to ensue as a side effect and cannot be pursued directly.
Most importantly, behavior is induced by reasons, not causes.