But in the same time,
TiffanyMonroe isn't totally wrong.
Each choice you make close a door ; perhaps not entirely, but what was an opened door is now a door ajar. And we already had one decisive choice regarding Trisha, when she came flirting in the Power Room.
You've 5 days on Ophion, and four (five ? don't remember for sure) period by day ; you'll not be able to pursue all the girls and, like LaFontaine's hare, the later you start, the lower are your chance to win . Plus, depending of the girl, your progress with her, and the context, a girl can take the priority over an other one. Exactly like Chris obviously abusing of her rank to have her drink
alone with femBob ; I mean, you're supposed to have had as much beer as Annie (cheater !!), yet for you it's not a problem and some wine in top of this is good... as long as it's with her.
But well, it's Chris, I forgive her
In top of that, you've to take into account the girl's intent.
Annie want to pass time, in a pleasurable way if possible. As pissed as she can be if you don't choose her, tomorrow is another day, where she'll be as bored as she is today ; and potentially more frustrated if the reparation of the Vanguard don't progress. The door will surely be still opened tomorrow, unless perhaps if you're a female MC since it's more difficult to turn her into a spaghetti.
And the same apply for Sarah and Chris. They've finished their mission, and have five days to kill before the next one (returning to the Intrepid) start. Whatever you've to offer as distraction will be welcomed, even if you dismissed them previously. You'll probably progress less, but you'll still have content to enjoy.
But for the girls on Ophion, it's something totally different. They have their motive (always assume that they have at least one more than you seen) and dismissing them can be seen as rude, or not fitting their agenda, closing definitively the door.