IIRC it had to do with fuel and the mass of the thing. There wasnt enough fuel to break earth's gravity to get to the moon and also slow back down on the return trip. The lunar lander and command module weigh a fraction of what the shuttle weighs (CSM + lander were 100k kg loaded, while shuttle was 2m kg dry), and most of the CSM's weight (over half) at launch was fuel.
Getting a shuttle to the moon and back would essentially require another big orange tank waiting for it in space after launch. It could be done but it would be prohibitively expensive.
IIRC it had to do with fuel and the mass of the thing. There wasnt enough fuel to break earth's gravity to get to the moon and also slow back down on the return trip. The lunar lander and command module weigh a fraction of what the shuttle weighs (CSM + lander were 100k kg loaded, while shuttle was 2m kg dry), and most of the CSM's weight (over half) at launch was fuel.
Getting a shuttle to the moon and back would essentially require another big orange tank waiting for it in space after launch. It could be done but it would be prohibitively expensive.