There are several points in Star Trek canon which state that transporters function by digitising the target’s molecular makeup, transferring that into temporary

There are several points in Star Trek canon which state that transporters function by digitising the target’s molecular makeup, transferring that into temporary storage, and then reconstructing it at the desired location. This does for me raise the question of why people routinely die on away missions. Just keep some storage somewhere on the ship which stores a copy of the person at the point in time they transported down, and if they get injured restore from that backup.