Orbiting but not Landing on Mars
If a first crewed flight to Mars only involves orbiting the red planet, visiting Phobos but not landing on the planet, it does make sense for engineering, medical, and costs reasons (fewer astronauts, far less mass).
Landing on Mars means having to return back from the surface, with a considerable amount of Delta V.
It also means having to spend a lot longer than a month to make it cost effective, while an orbital flight can last one month to take advantage of the same launch window for a quick return.
And we'd find out how to deal with the time spent for the trip, the distance from the Earth, from the Sun.
Raoul