Everyone in the anime industry is noble, idealistic and determined to do the best work possible. It's a tough business, but we can make great anime if we all work together! Everyone's nice! Let's all be friends!
Girlish Number is not that show.
Chitose is a self-obsessed bitch who doesn't care if her show fails, just so long as lots of people are following her on Twitter. She didn't bother reading the books it's based on and she doesn't think she needs to do any work to prepare for her performances. It's not about acting! It's about being famous! It'll take her twelve episodes of character growth to reach the point of merely being dumb and insensitive.
Kuzu is a producer and your worst nightmare. He palms off all the work on others, laughing a lot and thinking he's a genius. He's full of plans, but these might involve using the spare budget to take the girls to a tropical resort. His responsibility is managing the cliff-edge production schedule, but all he does is keep promising that it'll be okay while doing nothing. Meanwhile the animation staff are having nervous breakdowns because their art is garbage. (Kuzu didn't give them enough time to produce anything else.)
"Kuzu" means "rubbish" in Japanese, by the way. People call him Mr. Trash and when he introduces himself, his words mean "I'm the Rubbish Producer".
It's a show of two halves. The first half is black comedy, as we gawp at the monsters. We're here to watch it crash and burn. Monster egos + anime = ouch. Self-congratulating idiots launch a new show (called Kuusure), casting a bunch of cute girls without bothering to see if they can act. Chitose is chosen as the lead, basically at random. She thinks this means she's a star and lets it go to her head, even though her acting's dire and she's a novice in her first significant role. Pretty much the only unprofessional behaviour that's not portrayed in Girlish Number is the trading of sexual favours. (It's a completely chaste show and family-friendly, although what it's saying is lacerating.)
This would have been excruciating had Chitose been ruining the work of a team with professionalism and integrity, but Kuusure is so obviously doomed that you can only laugh. The author of the source novels goes into shock and becomes mentally unstable. Thinking about it, what's fascinating is that I never gave up and stopped watching because I hated these people. I liked them, even as I despised them. Chitose and Kuzu are selfish and appalling, yes, but they're also refreshingly brazen about it, while also being positive, cheerful and full of energy. They know no shame. Furthermore Chitose's brother/manager, Gojo, is brutally rude to her at all times and keeps telling her the truth, i.e. she's lazy, with no real talent and a bad personality.
It also helps that there are five girls in Kuusure's main cast and four of them are lovely. Well, maybe three. (Momoka's a bit of a bitch underneath that ever-smiling, super-professional surface.) Or perhaps two. (Kazuha is intimidatingly serious about her acting and will only smile at you if she's being paid for it.)
But I did care about them. The girls are funny together. Chitose doesn't have enough self-awareness to put up a professional-looking mask, even onstage, but this makes her oddly endearing. She's also capable, very occasionally, of saving a bad situation through sheer brass neck.
That's the first half. The second half lets the characters grow.
Momoka and Kazuha have issues with their parents. They help each other address these. Momoka starts caring about people and Kazuha starts to like her colleagues. Yae and Koto (Chitose's fellow novices) work hard and start building careers, getting regular work elsewhere.
Chitose's career, on the other hand, goes nowhere. She gets as much work as you'd expect, given her attitude and work ethic. Eventually this starts getting to her. She really hates losing and even she eventually becomes capable of seeing what's in front of her face. Reality smacks her hard and she grows. She'll still be crass, but at least she'll be more genuine and warm about it.
This is nice to watch. Girlish Number, against all expectations, turns into a sincere show that cares about its characters. It's a screeching U-turn, but they make it work.
Overall, it's a remarkable series and a gleefully acidic counterpoint to the idealism of shows like Shirobako, Seiyu's Life! and New Game!. It's capable of showing you things about the industry you'd never have expected, e.g. criteria for what gets a second season. It's funny, animated with lots of life and some immortal facial expressions. It's quite a ride.