I think a lot of answers have existed for that question. In the context of this thread, lets say you are a species which stepped out of your planet, there are

I think a lot of answers have existed for that question. In the context of this thread, lets say you are a species which stepped out of your planet, there are plenty of asteroids, and even planets lying around you can mine for resources. You settle billions of your kind in space. You are not running out resources and have no motivation beyond research and science to venture out a little far. Would you, such a race, want to travel interstellar distances? You would travel far distances by organic growth. Also its likely how old the universe is anybody who didn't kill themselves to extinction, is likely at our phase of development. And is likely asking the same questions as us. Those beyond our phase of development are hiding for a good reason.