Currently a manned mission can end in either total success or total catastrophic failure (for the most part). The most extreme example I've encountered is a failed science step on a joint mission ending in the death of both crews. All-or-nothing failures can be a little nonsensical at times.
I'm not arguing against mishaps, but rather for an option of attempting to return crew / scrub the mission when feasible (obviously there are situations where this would never be possible). To provide some examples of what I'm thinking-
- 1) Astronaut on duration step gets space sickness ---> skip to Reentry Preparations step (and duration goal is failed)
2) Lunar lander crashes ---> Apollo capsule skips to Trans-Earth-Injection step (minus two crewmembers)