Do you think you're a great boss? Probably--most people do. But there are some extremely common mistakes that keep good bosses from being great bosses. There's a good chance you're doing at least some of these things wrong--even though you have the best possible intentions. Make enough of them, and you can wind up being the boss no one wants to work for.

But it doesn't have to be that way. That's the word from Kim Scott, former executive at Apple and Google, and author of the bestseller Radical Candor: Be a Kickass Boss without Losing your Humanity. In a presentation at the recent Qualtrics Insight Summit, Scott shared what she's learned about the biggest mistakes you may be making as a boss:

1. Failing to value people who don't want promotions.

Scott draws a distinction between what she calls "rock stars" and "superstars." Superstars are ambitious high achievers, and if you have one working for you, you know you need to start thinking about who can take over that job because most superstars move up to higher positions very quickly.

On the other hand, Scott says, "Rock stars are like the Rock of Gibraltar. They love their work and want to keep doing it." They usually aren't eyeing the next rung on the ladder, and so they can create stability and continuity in your workplace.

Scott had one such rock star working on a customer service team, she says. When the position of team leader opened up, she offered him the job, but he said no. "He said, 'What I want to be is a Broadway star, so I want to be able to depend on leaving every evening at 5,'" she explains. Despite this lack of ambition, he was beloved by the company's customers who not only gave him high ratings but also often sent baked goods.

But the new team leader she hired had little respect for customer service people and thought the aspiring performer must be a B player. The rock star became unhappy and quit. "The baked goods stopped coming," Scott recalls. "Soon, it was reflected in our revenue."

2. Focusing on future potential rather than current performance.

That was the mistake the new team leader made, Scott explains. "The way we do talent planning is often dead wrong," she says. "Too often, on the vertical axis, the word we use is 'potential.' There are two things wrong with that. First, you're assigning people low potential, which causes you to undervalue your rock stars. Instead, think about who's on a steep growth trajectory and who's on a gradual one, and remember that there's nothing good or bad about either. All of us, at one point or another, wind up on both."

3. Assuming that people's ambitions don't change.

In fact, depending where we are in our lives and our careers, we will likely switch back and forth between rock stars and superstars many times. Scott herself had to pass up a big opportunity when she was asked if she'd like to be considered for the job of Twitter CEO. It was the kind of opportunity she would normally never pass up--but at the time she was in the midst of a high-risk pregnancy with twins. When she asked her doctor for advice, the doctor asked whether the job was more important to her than her babies' healthy development. That did it: Scott declined the opportunity.

4. Promoting people to the wrong job.

There are many situations when promoting someone is the wrong thing to do, Scott says. "Some people are at a phase in life when they don't want promotions. I knew someone who had carefully planned his life so that when his first child was born he knew his job really well so he could go home to his family every night. Then two months after the child was born, his manager told him he was getting a promotion that he couldn't refuse. So he quit."

Scott herself remembers promoting a woman who was really good with people into a mostly analytical job, and then giving that woman the worst performance review she'd ever had when it turned out she couldn't do the new job well. "Next quarter it wasn't better, and I realized I had put her in the wrong job," Scott says. "Her bad performance was my fault, but she was such a team player that she never said so."

Part of the problem is that many bosses make promotion the only path to advancement, Scott says. "If promotion is the only way to get higher pay or greater responsibility, you'll create promotion obsession on your team."

5. Believing you have A and B players.

If this is how you view your team, you should revise your thinking at once, Scott advises. "There is no such thing as a B player," she says. "If someone is not doing work as good as they could be, look at yourself in the mirror." Perhaps you've placed someone in the wrong role. Perhaps you aren't providing the right kind of guidance and motivation. "Give them radical candor, give them some education, give them some stretch projects, and give them the chance to take a risk and fail," she says.

What if you do all that, and nothing changes? "Then you have to have a tough conversation because it's hard to tell someone that just OK is not OK," Scott says. Whatever you do, don't put off that difficult conversation. "A manager who allows someone to go on forever doing good but not great work is not doing that person a favor," she says. "There is no greater pleasure than doing great work, and everyone deserves that."

6. Being an absentee boss.

"Some people think you should ignore your top performers, which is like marrying the perfect person and then not spending another minute with them," Scott says. "People think: 'I don't want to micro-manage, so I'll be an absentee boss.'" But, she says, there's a difference between being a micro-manager, an absentee boss, or a thought partner, which is what the best bosses are. Absentee bosses leave their best employees to fend for themselves. Micro-managers retain control by hoarding information. "Thought partners are curious and they ask about relevant details," Scott says. "They also know more context, and they share that knowledge."

7. Not having the right conversations.

You need to take some time to get to know the people who work for you and especially what their goals and hopes are, Scott says. These are conversations that should take place outside the context of a performance review. Plan to spend at least 45 minutes or so getting to know the person outside the context of work.

Obviously, you need to do this with some sensitivity, and if employees don't want to talk about some aspects of their lives, you should back off immediately, Scott advises. "Focus on the pivots people made in their lives and ask why they made those changes. You will be able to deduce what the employee values."

For example, let's say someone tells you they switched from cheerleading to swimming during high school. If you ask why, they may tell you that they liked the camaraderie of cheerleading, but couldn't see the kind of improvement every day that they could with swimming laps. So now you know: This is probably someone who needs to see measurable results. "The richness of the story will give you a whole different understanding than you'd get by asking someone what motivates them at work," Scott says.