6 Career-Ending Mistakes You Should Never Make on the Job

There's more than enough advice out there about what you should do when you land a job and want to jumpstart a successful career: Show up on time, do what you say you'll do, and be curious (among other great suggestions).

But have you ever wondered if there was a list of things you definitely should not do?

As it turns out, your HR manager has a list like that! And to get some insight on what's likely on that list, we connected with Kate Kastenbaum, seasoned HR Director at Certain, Inc.

If you're trying to figure out which behaviors will get you ahead at work – and which you should avoid at all cost – here's are six slides of things you should never do on the job.

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Never hold a grudge or let a problem fester.

"If someone wronged you and you hold a grudge towards them, you tend to avoid them," says Kastenbaum. "That can make it really difficult to get your day-to-day job done because you're naturally less productive when you're busy creating work-arounds."

The solution? Deal with your issue face to face. Put personal feelings aside and focus on the work: "You may not personally like everyone, but you have to be willing to work with everyone," Kastenbaum continues. "People want to work with a team player. Avoiding the problem shows a lack of maturity and difficulty handling challenging situations."

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Don't avoid your boss.

If you're more inclined to be open and honest with your peers, that's a mistake. Your boss writes your performance reviews and often decides how much you get paid. She can be your advocate for your career – but only if you have a strong relationship.

"It's one thing to let a problem fester with a coworker you rarely see, but it's damaging when it comes to your boss," says Kastenbaum. "Open and honest communication with your manager is vital. If you have an issue and don't bring it up right away, you're not using your manager for what they're there for, which is to help you navigate problems and guide you to the answer."

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Don't ask your coworkers for drugs.

Before you laugh, it's a true story! While many company cultures work hard to build a close and friendly team, sometimes that can lead employees to feeling a little too friendly. Don't let feelings of closeness blur the professional boundaries that must always be present when working with managers, coworkers, and clients.

"It's the season for holiday and event parties, and it's natural to want to go out with peers and have a good time," says Kastenbaum. "But even if you feel relaxed with your coworkers, remember that there's always someone watching. Don't get drunk, abuse drugs, or abuse the situation you're in because the truth will come out and your career and work relationships will pay the price."

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Never say, "You're wrong."

The customer may not always be right, but there's never an appropriate time to flat out tell a manager, coworker, or customer they are wrong. Even if the person you're working with is obviously mistaken, mediate the situation by assuming that the problem is real or the error is a mistake.

"Always assume the customer is right, and give your coworker the benefit of the doubt," Kastenbaum elaborates. " As you work through the solution you can clarify or help them realize where the error is, but if you start the conversation off with an accusation you won't get very far in the discussion."

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Never make a habit of being arrogant or disrespectful.

You can be the best of the best in your field, but if no one wants to work with you, you won't get much done. While even the most well-intentioned among us can have a bad day and be too short or too egotistical with a coworker or boss, it's in your best interest to not make it a habit.

"No one wants to work with the kind of person who has his nose in the air or frequently disrespects others," says Kastenbaum. "No matter how prestigious your background or important your project, you'll build much better relationships if you show respect and humility in your interactions with others. Frankly, if you can't get along with the janitor, then you won't get along with the CEO either."

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Don’t leave your personal career development to your boss.

Don't be afraid to talk to your boss about how you can make a difference and grow in your career – and don't expect your boss to be the one who initiates that conversation.

"Your manager can help you, advocate for you, and look out for opportunities, but your manager does not own your career," says Kastenbaum. "If you don't initiate those conversations about what you want to learn or where you want to go in your career, they may never happen."

Sometimes what not to do is just as important as what to do. Use this list to double-check that you aren't making any of these mistakes in your own career.

By Sarah Greesonbach