You're rolling unlucky. It is a D20 roll, and you only need to roll at or below your stat. At a 10, that should be 50% success on average.
File Clerk might be a better option if you have good Awareness, as it has the same options to build favor and does not carry the chance to lose favor on a critical failure.
All of Manners' favor changes occur at the Globex jobs.
Figures. My data set is small, only ~10 data points, but even so my luck is sucky. Looking at the code,
Code:
$ rng_value = renpy.random.randint(1, 20)
$ var1=7
if player.power_WIT>=1:
$ var1+=2
$ var1+=player.concentration
$ var1+=player.MB
if rng_value<=player.concentration and rng_value<=var1:
My Billy currently should be var1 = 7 + 2 + 10 + 3 == 22. So he can't fail and should get 50% critical success. I don't think I can potentially push Concentration any higher until Brilliance enters the game. *edit* this Billy doesn't have Kinesis yet, so Concentration can go to 11 and drop the number of shifts to 37.
So currently, I'm looking at an expected 40 shifts to achieve the favor to buy the better job if I don't try anything sneaky with Alice. Awareness max is a point lower because power bonuses are a point lower so at best it'd take 45 shifts if it were maxed, which it isn't on my current Billy.
8 weeks of grind it is, 10 actually. as I can't afford to cut school on Tuesdays because I need to keep attending the club activities. Maybe I'll use this time to cure Anne of her deep-seated mental illness.