Problem with Sync Reimport

I’m finding myself synchronizing problems, some products coming up as changed price, shipping no longer available, out of stock and reimport. my problem is on Reimport. Why do I have to re-edit the products images, description all over again. Every time everything changes or I’m missing something. It’s time consuming and frustrating. When Synchronizing does it changes any of the above. HOW does this work? from being overwhelmed and over worked?