Dual card slots doesn't necessarily solve the problem. The medium can be mishandled.
You could always use wi-fi to back up the shots in subjective real time. As to ruining shots... yeah,
it could have been processing, it could have been the film and/or film cartridges itself. (Depending on the camera and film. ) With 35mm if you have an older reusable case, light can get in. On 120mm rolls this too could be a problem. If the film wasn't inserted properly...that too could cause errors. (Think about loading a roll under fire.) Plates are another story and handling of them could pose an issue even before the shot.
My dad had a "pocket" camera that he took with him. Of course that was in Dec '44 just in time to help wrap up the battle of the bulge and then some. (14th Armor) The irony... he captured images of people during a time that he wanted to forget. (remembering them, brought back memories of how some of them died..)
But back to the point.
Back in the '30s there were some incredible shots taken with a pocket 35mm camera. A Leica I think .
In focus with a good depth of field. (A skating waiter??? IIRC)
It was well framed and told a story.
Some of the best boxing photos were taken with 4x5s and a flash.
When I was growing up in the 70's in one of the classes on composition, we had a guest speaker who was a professional sports photographer. One thing he said was that getting a good shot meant being in the right place at the right time. That meant planning. He only shot 6-12 photos during a game. Ansel Adams also took a lot of time setting up and waiting for the right shot.
Which goes to another point. One can argue that today's smart phones are ruining photography. Rather than take your time, frame the subject and create a good shot, people just point and click taking multiple shots hoping something works out.
Its a give and take world.