Most articles that talk about leadership attributes focus on the positive ones, the things you SHOULD do to be an effective leader. Since I am always trying to give you a unique perspective, I'm going to take a different path. I want to talk to you about the worst qualities of a truly bad leader. Now there are many qualities that are situational. Some teams and situations demand different things. I'm going to exclusively focus on those leadership qualities that I think are terrible no matter what the situation. So here we go.
A truly terrible leader thinks they are always the smartest person in the room. I put this first because I believe this is the single worst quality a leader can have. Yes, there is a hint of arrogance to this attitude that can certainly be problematic, but that's not why it tops my list. The real issue is that it shows that the person doesn't understand what leadership is in the first place. Good leadership is about hiring the smartest people, not being the smartest person. Your job is to find people who know more than you and build a cohesive team that allows you to accomplish your goals. Your job is to surface the great ideas other people have and make sure to knock down the roadblocks that would prevent those ideas from succeeding.
Similarly, a truly terrible leader thinks they have to make every decision. These first two qualities often go hand-in-hand but not always. The person who feels they need to be involved in every decision speaks to a person who doesn't trust the people they hired to do their jobs, and if that's the case, why are they on the team to begin with? This approach tends to lead to micromanagement, which is an incredibly inefficient way to manage a team and usually leads to sub-optimal results. I have a whole article on the dangers of micromanagement, so I won't repeat myself here. What I will say is that this does not mean you should be completely hands off. Obviously, you should be part of the discussion, and it's certainly a good idea to review the decisions made to make sure they are in line with specific goals and overarching objectives. But think of it more as guiding people rather than making decisions for them.
A truly terrible leader emphasizes process over outcomes. While some process is necessary, of course it is, focusing on it leads to developing specific processes to handle edge cases that only slow down the team. I do want to be careful about this because I'm not saying a good leader doesn't think about process at all. I'm simply saying a really bad leader is obsessed with it.
A truly terrible leader takes credit for everything and shares the credit with no one. While this kind of deception might allow the person to progress up the corporate ladder fast, it will fail them once they get to that position they so desperately craved. We don't work in a vacuum, and all those people they stepped on to get ahead will subtly (or not so subtly sometimes) sabotage that leader any chance they get. And who can blame them? On the flip side, when you build other people up and give them credit for their hard work, it makes your life easier in the long run because those people are willing to go the extra mile for you.
A truly terrible leader falls back on phrases like "...because I'm your boss" or "...because I said so." These are signs of lazy leadership. The vast majority of times this comes up is because someone is trying to understand a process or decision, not because they are simply trying to be contradictory. If you can't explain the why to them, you certainly can't expect them to execute well.
These are my top five. I'm sure there are more you can think of. Let me know which traits/behaviors you think are worse than the ones I've mentioned.