It is useful, there are a lot of science projects going on as well as studying the astronauts themselves to learn more about how people can survive for long per

It is useful, there are a lot of science projects going on as well as studying the astronauts themselves to learn more about how people can survive for long periods without gravity. Sure robotic missions are great for exploration but I'd imagine for a lot of experiments going on on the ISS having a human there to make changes would dramatically cut the cost of having to send up fully automated experiments.