There is no secret that there are a lot of moving parts throughout the job search process. Crafting resumes, practicing your pitch, or planning questions and answers for your interviewer are just a few things you are responsible for. Unfortunately, sometimes it can be easy to overlook ‘small’ things that can impact your candidacy as a whole. As a result, certain job rejections can be puzzling—especially when you’re not sure what went wrong.

To ensure you’re aware of what not to do, here are 10 reasons why you might not have been hired:

1. You gave a bad first impression

It’s no surprise that first impressions mean a lot during the interview process. Although your actual interview might have gone well, the little things you did might come back to haunt you. For example, you arrived five minutes late, your attire wasn’t entirely professional, or you were fidgety. Here are some other ways to make a poor first impression.

2. You didn’t follow directions

“Please send your resume in a pdf format.” “Please bring at least 5 copies of your resume to the interview.” These are examples of typical requests a hiring manager might have throughout the interview process. However, if you chose to send your resume as a ‘doc’ or forgot their specific request, this will speak to a lack of attention to detail—a quality that employers typically expect in new hires.

3. You were unprepared

You should always be putting your best foot forward when entering an interview. Therefore, regardless of what stage of the interview process you are in, not preparing answers to common interview questions, or thoughtful questions for your interviewer can be an immediate deal breaker.

4. You lied about something

Lying about anything throughout the interview process never ends well for the candidate, as employers have a variety of ways to fact-check and verify the things you’ve said. For starters, avoid lying about your education, experience, or personal references.

5. You weren’t a good cultural fit

Keep in mind, “fit” plays a major role when employers evaluate whether they want to hire certain candidates. Whether you prefer working in a certain type of environment, or working with a particular management style, if your prospective employer practices the opposite, this could be the making for a poor cultural fit down the road.

6. You were too casual or overconfident

If your interview seems to be going well, it can be tempting to let your guard down and start building a friendlier rapport with your interviewer. However, becoming too casual by using slang words or making jokes may subsequently depict you as an overly confident candidate. As a result, it makes you sound as if you’re playing around and not taking the role seriously.

7. You have an unprofessional online presence

While social media accounts serve as a great way for you to express your ideas and opinions, without given the proper context, some things can be misconstrued and work against you throughout the interview process. Therefore, if a quick Google search reveals that your online presence might be an issue; this is easy grounds for a hiring manager to move on with another candidate.

8. You didn’t send a ‘thank you’ note or follow up

Whether you have gone through a first-round phone screen, or have made it to the final interview stage, writing a thank you note to the hiring manager is more than a best practice; it’s a move that conveys your respect for your interviewer’s time, demonstrates your interest in the role, and keeps you top of mind during the decision making process. Failing to send a thank you note will be viewed as a major red flag to a prospective employer. Remember, if a recruiter has coordinated your interview for you, they will most likely facilitate all of the conversations outlining next steps.

9. You didn’t sell yourself well enough

All too often, exceptional candidates miss out on great opportunities because they don’t use their interview time strategically enough to sell their skills and experience. Instead of rehashing the skills and experience already listed on your resume, clearly articulate what about your background specifically makes you the best candidate.

10. You didn’t connect with the hiring manager

At the end of the day, the connection you share with your interviewer will play a major role in their decision to hire you or not. Although you might be qualified, have stellar credentials, and were enthusiastic throughout the interview, if the chemistry isn’t there, there’s not much you can control about this.