Question on uploading photos to site

I got a question why is it when I upload photos to site from my phone or iPad the pictures look perfectly clear on ipad but when I upload them on the site they look like crap. Maybe I’m doing something wrong hopefully you guys can help me

No I was clicking full image and letting it load and then submit

I just tried loading a photo by hitting submit rather than full image and it still looks like crap

I just uploaded them using photo bucket and there so much more clear