The joy of being a performer comes from hearing the audience appreciate you in the moment. You sing, dance, make music, and the crowd provides validation through applause.
If you work in a field without this instant feedback, you may never know the reaction of the person on the other side. That website, article, logo; you'll know what the client or boss thinks, but what about the person seeing it in a coffee shop?
You'll never know the value of what you do until you meet someone affected by it. But trust that someone will see your work, and your effort will have some affect on their experience. Imagine that person seeing the finished project as you work on it in solitude.