There is a possibility that keeping your photos in raw form will protect from major copy errors, but in all situations of moving bits in a data stream, there is the possibility of transient error. Jpg was considered lossy as it could not fully recreate the the full raw data. 25mb or more  of raw image data per image is, or was, a hefty size to move across the bus in early days, much less across the internet.  Now we have so called lossless JPEG, however its accuracy is based on predictive sampling rather than a pure collection of bits per pixel.

Humans lose thousands of skin cells a day, yet the fabric of the persona stays the same. I think photo data is a little the same, a few stray bits lost here or there won't change the picture that much. However it is possible to corrupt that significant bit which would make decoding the picture impossible.