The close of a calendar year is a good time to reflect on the previous 12 months and devise a plan to improve things going forward. Whether you experienced a few career mishaps this past year or progressed as expected, it never hurts to strive to do better as a new year kicks off. With that in mind, here are a few critical mistakes you should avoid next year at all costs.

1. Avoiding risks

It's not easy to step outside your comfort zone and put yourself in a position where you might fail. On the other hand, if you don't take any risks on the job, you might quickly end up stuck in a rut. The next time a great idea pops into your head, don't ignore it. Rather, run with it and see where it leads. Even if it doesn't work out, your boss likely will appreciate your ingenuity.

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2. Not continuing to learn

It's easy enough to coast at work when things are going smoothly. After all, why shake things up when your boss seems pleased with your performance?

But if you don't push yourself to keep learning and growing professionally, you're likely to stunt your career growth and miss out on key opportunities to get promoted. So figure out in which areas you're lacking knowledge and take steps to bridge those gaps, whether it means signing up for courses, attending conferences and seminars, or enlisting the help of a mentor.

3. Getting easily flustered

It's hard to keep your cool at work when deadlines loom and projects are dumped on you at the last minute. But if you don't figure out a way to cope with job-related stress, you're less likely to move forward at your company. As you ease your way into the new year, practice different stress-relief techniques until you find the one that's most effective for you. At the same time, train your brain to better handle heated situations so that you come off as competent and collected.

4. Neglecting your business relationships

When it comes to furthering your career, the people you know are often just as important, if not more so, than the things you know. That's why you can't afford to neglect your business contacts, even if making time for them is challenging in its own right. Though you may not manage to sit down for lunch with your various associates on a monthly basis, you should, at the very least, reach out to each person in your network every few months to check in -- especially since you never know when those folks might have a solid job opportunity that's perfect for you.

5. Allowing yourself to be unhappy at work

It's an unfortunate fact that a large chunk of workers today are unhappy at their jobs. If you've taken steps to make your role better and nothing seems to be doing the trick, don't resign yourself to another 12 months (or more) of misery. Instead, dust off your resume, reach out to your contacts, and seek out a job that you'll find more fulfilling. The longer you allow yourself to stay at a job that makes you miserable, the more your performance is likely to suffer, and that's a good way to hurt your reputation and get yourself fired.

6. Not asking for a raise

Many people shy away from negotiating salary at work because they don't want to come off as greedy or anger their managers. But you know what they say: If you don't ask, you (often) don't get.

Furthermore, if you approach that conversation the right way, you can pull it off in a manner that doesn't damage your relationship with your boss. That means researching salary data so you're able to present a reasonable number to your manager and going in prepared with a list of reasons you deserve a boost. Either way, don't avoid that discussion just because it makes you uncomfortable. In doing so, you'll not only potentially lose out on money that could've been yours, but also create a situation where you might start to resent coming to work.

With a new year right around the corner, now's the time to evaluate your on-the-job habits and strive to do better. Steer clear of these blunders in the coming year and with any luck, 2019 will be your most successful one yet.

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