I’m assuming you want something more involved than, “because I enjoyed it,” eh, random Anon?
Well, firstly, Henry Cavill’s performance was great. I really liked him as Clark. And also the Smallville scenes where Clark was younger… I’ve always felt like coming into his powers would be confusing and scary (maybe even almost traumatic) for Clark and this movie showed that. There’s also the fact that this was one of the first versions of a Superman origin story that gave Lara a more active role, rather than just being Jor-El’s wife and little more. I really appreciated getting to see her (and in fact, she was my favorite thing about the Krypton sequence). Clark’s relationship with Martha was lovely as well. There were other things I enjoyed about it but these were the first to come to mind.
Was it a perfect movie? No, not at all… and I never said it was. But I did like it… though I suppose I understand why a lot of people didn’t.