We all know that the journey of a developer is one that requires constant learning, no matter how long you have been on the road. However, what is that one thing that you want to achieve, and when you do achieve it, you can sit back and say, "Ahhh.. I have finally fulfilled my purpose as a developer!"
(It can be directly or indirectly related to being a developer)
Personally for me, I would like to build something that is beneficial to the society. It may not be just one thing, but a combination of things. I have not exactly pin-pointed what I would like to make, but I guess that gives me the freedom to explore more technologies before settling on a problem and crafting a solution for it. As a junior developer with still a lot to learn, that is my end goal, and it is what motivates me to improve myself as a developer :D