Coworkers don't always have to be friends. They don't even have to like each other per se. They do, however, need to coexist peacefully enough to collaborate as needed, so if your behavior isn't allowing for that, it could spell trouble for your career. With that in mind, here are a few things you might inadvertently -- or intentionally -- be doing that drive your colleagues to dread being in the same room as you. Pay attention!

1. Brag about your accomplishments

It's OK to be proud of the things you do at work, but it's another thing to constantly give yourself pats on the back in public. Show off too much about the brilliant way you handle presentations or create killer marketing campaigns, and your colleagues will not only cease to give you props when they're due, but secretly start wishing for you to fail.

Man pointing at a woman on her mobile phone


2. Be a know-it-all

There's nothing wrong with being smart and well-educated in your field. But when you cross the line into making others out to be imbeciles in the face of your vast knowledge, you risk alienating them indefinitely. Instead, hear your coworkers out before shooting down their ideas, and present your counterarguments respectfully.

3. Fail to give credit where it's due

Maybe your colleague mentioned an idea in passing, and you've come up with your own way to expand on it and make it even better. While you may have built on that concept solo, attempting to pass it off as your own idea without acknowledging your coworker's contribution is a downright awful thing to do. The same applies any time you fail to give credit to colleagues who lend to your own successes.

4. Be a needless whistleblower

It's one thing to catch someone stealing expensive company property or divulging trade secrets for cash and feel compelled to report it. But in the absence of something clearly unscrupulous, there's no need to send a memo to HR every time you see someone pocketing a package of sticky notes or lifting the occasion box of pens. Chances are, your company won't care, your coworkers will get mad, and you'll only come off as a tattletale.

5. Fall down on deadlines

When you work on a team, you're bound to have others counting on you to get things done. So when you slack off and fail to meet deadlines, you not only jeopardize your good standing at work, but put others in a position where they need to scramble and get stressed in the process. The next time you find yourself procrastinating on a project you promised others you'd do, snap out of it and get moving. Otherwise, expect a steady stream of much-deserved dirty looks from your colleagues.

6. Complain constantly

It's hard to remain positive all the time at the office when deadlines loom and the pressure never seems to subside. But if you get into the habit of griping about every single aspect of work that rubs you the wrong way, your coworkers are apt to get sick of hearing you moan. So be selective in your complaints. If your boss asks you to sacrifice your weekend to help with a last-minute report, by all means, air that grievance. But don't whine about every single task you're asked to undertake, because after a short while, it'll just get old.

7. Steal other people's food

This one's just a no-brainer. No matter how hungry and swamped you are, if you neglected to brown-bag your own lunch and don't have time to run out and grab something, you must resist the urge to scarf down whatever unlabeled lunch you find sitting around in the company fridge. Stealing other people's food is by no means acceptable, so if you're in a pinch, beg a coworker to pick up a meal for you, or take seven seconds to order one in. Or, purchase a candy bar from the vending machine and call it a day.

Having a good relationship with your colleagues can not only make for a more pleasant work experience, but in some cases help further your career. If you've been known to engage in any of the above habits, you'd be wise to change your ways immediately. Otherwise, don't be surprised when your coworkers start taking steps to avoid you.