Simply opening or displaying a JPEG image doesn’t harm it in any way. Saving an image repeatedly during the same editing session without ever closing the image will not accumulate a loss in quality.

Why do JPEGs lose quality over time?

An image loses the quality the moment it is captured, rendered and saved into your phone or camera’s memory as a JPEG file. When an image is saved as a JPEG, it is compressed. This means that part of the original information is forever lost. This is why JPEG images are so fragile and easily break up if over-edited.

Does JPEG lose quality?

The quality will not change if you copy or move the file. If you open it and save over it, it may or may not degrade. The compression (encoding) is a process that analyzes the picture to work out a mathematical description of the picture that can be represented with fewer bytes than the original.