Goran Milic, Zagreb, Croatia

A NOW, why would you ask that question? Certainly not because you want to be a lousy leader yourself! It can only be because you're checking your instincts about someone you know. Maybe even the person who writes your paycheque.

And in that, you're not alone. We have written in a previous column about employees who are inveterate "boss haters" but we've never given bad bosses their due. So here are a few of the most familiar ways leaders can get it wrong, and too often do.

The first, and perhaps most frustrating way, that some people blow leadership is by being know-it-alls.

They can tell you how the world works, what corporate is thinking, how it will backfire if you try this or that and why you can't change the product one tiny iota.

Sometimes, these blowhards get their swagger from a few positive experiences. But usually they're just victims of their own bad personalities. And you and your company are victims too. Because knowit-alls aren't just insufferable, they're dangerous.

They don't listen, and that "deafness" makes it very hard for new ideas to get heard, debated, expanded or improved. No single person, no matter how smart, can take a business to its apex.

For that, you need every voice heard. And know-it-all leadership creates a deadly silence.

If know-it-alls are too much in your face, a second kind of lousy leader is too little. We're talking about emotionally distant bosses . . .the type that are just more comfortable behind closed doors than mucking it out with the team.

Sure, these remote leaders attend meetings and other requisite functions, but they'd rather be staring into their computers. And if possible, all the messy, sweaty people stuff would be delegated to human resources managers on another floor.

Like know-it-alls, this breed of leader is dangerous, but for a different reason.

They don't engage, which means they can't inspire.

That's a big problem.

Leaders, after all, need followers to get anything done. And followers need passion for their fuel.

A third category of lousy leadership is comprised of bosses who are just plain jerks . . . nasty, bullying or insensitive, or all three.

As a reader wrote us recently, "My boss is abusive, by which I mean disrespectful, fingerpointing and sometimes even paranoid." Such leaders are usually protected from above because they deliver the numbers. But, with their destructive personalities, they rarely win their people's trust.

That's no way to run a business, which is why these types of leaders typically self-destruct. It's never as quickly as you'd hope. But unless they own the place, it does happen eventually.

The next type of lousy leadership is at the other end of the spectrum: being too nice.

These bosses have no edge, no capacity to make hard decisions. They say yes to the last person in their office, and then spend hours trying to clean up the confusion they've created.

Such bosses usually defend themselves by saying they're trying to build consensus.

What they really are is scared. Their real agenda is self-preservation . . . good old CYA.

Which leads to a final version of lousy leadership, which is not unrelated . . .bosses who do not have the guts to differentiate. The facts are, not all investment opportunities are created equal. But some leaders can't face into that reality, and so they sprinkle their resources like cheese on a pizza, a little bit everywhere.

As a result, promising growth opportunities too often don't get the outsized infusions of cash and people they need. If they did, someone might get offended during the resource allocation process; someone . . . as in the manager of a weak business or the sponsor of a dubious investment proposal.

But leaders who don't differentiate usually do the most damage when it comes to people. Unwilling to deliver candid, rigorous performance reviews, they give every employee the same kind of bland, mushy, "nice job" sign off. And when rewards are doled out, they give star performers not much more than the laggards.

Now, you can call this "egalitarian" approach kind or fair . . . and these lousy leaders usually do . . . but it's really just weakness. And, when it comes to building a thriving enterprise where people have an opportunity to grow and succeed, weakness just doesn't cut it.

Surely we could go on, but we'll end here with a caveat.

We hardly expect lousy leaders to read this column and see themselves. Part of being a lousy leader, no matter what the category, is lack of self-awareness.

But if you see your boss in the above groupings, take heart. When it's finally your turn to lead, you'll know what not to do.

Jack and Suzy Welch are the authors of the international best-seller Winning. You can email them questions at Winning@nytimes. com.