I had a boss that was completely horrible with communication. He'd give out new projects but be pretty much hands off for anything else unless deadlines weren't met. One of the staff he promoted to sysadmin was a master of bullshit. He was worthless and did nothing but make more work for us, but upper management loved the guy. He was the type that when one of us was nearing completion on something, he'd go demo it to senior staff in other departments without telling us so they thought he did it. He was very emotionally manipulative and would get a couple of the other guys to constantly cover him, and actively try to make you look bad if you didn't fall for his shit. It was causing our team which had functioned very well for years to fall apart.
I had a talk with the boss to explain what was happening and told him he needed to start being a lot more hands on, hire someone to manage us, or promote someone to a lead to coordinate things better. He decided he would promote me to management, but not until my annual review. In the mean time, I was to start taking his place at any meetings that would fall under my future roll. The problem was, I wasn't allowed to tell anyone why and he'd just tell everyone he was too busy to make the meeting so I was taking notes for him. So for 3 months not only is the bullshit admin causing stress and extra work, the other guys that were "on my side" are getting upset with me because I'm always going to executive meetings for apparently no reason.
Finally one Friday before he's leaving on a 2 week cruise he calls a staff meeting a few minutes before 5:00PM. He announces that he's making so me changes. Two lower guys are getting promoted to sysadmin to cover the work load and I'm going to be made manager. Bullshit admin is very visibly angry, and several are confused including myself. I had no input into the new team members, didn't know they were being promoted, and didn't know the announcement about myself being promoted was happening that day. He then immediately says, well I'm leaving for my cruise now, see you all in 2 weeks.
While he's gone I try to field a lot of issues, not knowing if I'm actually promoted yet or what. No paperwork was done, the boss said "going to be promoted" so I'm at a complete loss. Things just got worse when he got back. He continued to give new tasks to the other sysadmins directly rather than going to me or using the ticketing system. Then he'd ask me for an update on it when I had no idea it even existed. I talked to him again and asked why even promote me if he just ignored the fact that I was there. He said it was just habit for him and he'd try to be better. Things would work well for a few days, then go back to him ignoring me. Then he started complaining about my not doing manager tasks like employee reviews or paperwork I had no clue even existed. I'd been given zero direction or training with the promotion, so when he'd tell me I was behind on something, I'd have to ask him what the process was, where the forms were etc. He'd keep telling me "I figured you knew about it."
We'd had a similar problem with the help desk team. They'd been doing poorly and his last attempt to fix them was hiring someone who had zero computer or management experience. He kept that manager for about a year and they had fallen so badly the company hated them. When he got rid of that manager, he put the help desk under me as well. In front of them he told me that because the company thought they were so worthless, we didn't have approval to rehire to replace them. Because of that, I shouldn't write them up for anything or make any attempt to fire them because at least they can answer the phone. Of course they didn't improve under me, why would they? They'd been told they wouldn't be fired for any reason and I had no way to reprimand them that had any consequence.
Instead of having a chance to improve my team I was actively making things worse and I knew it. It felt horrible, but I was constantly blindsided by him and couldn't do much about it. I looked like a useless idiot with no clue what was going on and I essentially was. I'd lost respect from everyone below me. My stress levels were through the roof, and I was always certain I was going to be written up or fired when the boss would call me to his office. Whenever I'd bring up that I didn't think things were going well though, he'd always tell me what a great job he thought I was doing. Looking back at it, I don't think there was any possible way I could have been successful in the role and I don't know why I stuck it out as long as I did. Quitting that job was probably the best thing I've ever done for my mental health.