Simple, because you can create wonderful things that can help many people. Because it's like seeing the bones that hold the current society ... and even more impressive, you can add parts, repair or transform it to your liking.
I started about 3 years ago,When I had no idea what html was. Today I can create and implement by myself some moderately complex web applications.
More importantly, I know what to look for, where and how, I am not afraid to learn or ask.
NODE.JS, REACT, MONGO and the rest of API have been the center of my attention, now NEXT, DOCKER and GRAPHQL are on the list.