Generally, a failure happens to a few of the memory cells, and the camera will not give you a error. There is software that will let you reformat a card at low level, one cell at a time, and it will mark bad cells as unusable, so they are basically put out of the read / write process. Its silent though, so you don't know it happened.
Memory card bad cells which are not marked as bad by the controller can very hard to find, a 64GB card with a few bad cells might not save to one of them but infrequently, so you will think its a random error.
If you are getting corrupted images, a 2nd card should not be affected unless its a camera issue.
With a single card camera used in a situation where loss of images is critical, use raw + jpeg, its not likely that both will be corrupted by a random bad memory location.
If the card just fails, you will get a error, so pop in another and try to repeat the lost images.