Lorraine
Why did Lorraine fund a school without learning anything about running a school? She seems to use it as her personal PR machine, or worse, like when she had Janeece working for her instead of running the office. She has no qualifications as a teacher, but she's constantly trying to exclude students or change the curriculum, and when she doesn't get her way, she whines about the money she invested. How could Michael agree to a setup like that? Why does the new Waterloo Road not have a Board of Governors like the old one? (Could be because it's an independent school? Because it's in Scotland? I'm American, so I don't know exactly how these things work.)
I've just watched the entire show over the past few weeks, and I know it's not the most realistic thing ever, but Lorraine is just over-the-top stupid as a character. If she ran her business the way she runs the school, she'd be broke. (And she makes the move to Scotland even more ridiculous.)