I've yet to see any concrete reward listed for this. My second in command potato says something about risk vs reward, and I couldn't understand what either the risk or reward could be. Now it looks like you can fail a mission. Is that all? I was kind of hoping I could send my lalafail caster out alone on a mission never to return (since I can't find a way to simply remove them).

I guess the "higher chance of getting a new recruit" item can be considered a reward, but it still just feeds back into the system, like squad exp. Are there any tangible rewards that have an effect outside of the squad room?
Completed 8 or 9 challenge logs and still no new recruits since the first one. Yay RNG.