The subject is good, the dof is though the center part of the subject and I feel the whole can should be in focus. Photographing the can on the other axis would have been more effective IMO. I also see considerable noise in the image.
Too much JPEG compression. At a 49k file size you had a lot more overhead and could have avoided the loss of clarity that this suffered from excessive compression.
good find for this challenge - I too have a photo of cans in my "challenge portfolio" - it's very interesting what can be seen if one only takes the time to look :-)