I try to get the framing right in the camera. Sometimes I succeed. Sometimes not. Actually I enjoy fine-tuning the crop afterwards. It allows a perspective I may have not seen when shooting.
But here is a thought. What if the crop in the camera does not meet what you see? You're limited to the cameras format. What if the camera allowed you to format in the camera? Would you use it to get a better shot? If so, then what's wrong with cropping after the fact if the camera does not meet what you like to frame with it originally?
Here's another issue. What if the print format does not meet the negative or chromes format? What if you have the fortune to get it printed on a magazine cover? So you have to crop anyway.