When you’re looking for a new job, waiting to hear back from a hiring manager after an interview can be agonizing as the days and weeks go by.

5 job interview mistakes

Read more: U-Haul is hiring for work-at-home positions

If you never hear from them again, the experts at Glassdoor, a jobs and recruiting website, say you may want to take a critical look at your interview performance.

Here are five key reasons why you may not make it past the first interview:

1. You were not prepared

If you have a job interview coming up soon, don’t wing it. That’s a huge red flag!

As you prepare, you want to learn as much as you can about the position you’re applying for, the company, and the person who’ll be interviewing you.

The company’s website, as well as a basic Google search, are two great places to start.

“While some things like personality and culture fit are harder to control, anyone can look up interview questions on Glassdoor, check out the LinkedIn and Twitter profiles of your interviewers, and do a Google deep dive on all aspects of the industry,” said Glassdoor Senior Talent Acquisition Partner Jamie Hichens.

You should also arrive at your interview about 10 to 15 minutes early and bring at least three copies of your resume in case you need them.

2. You lacked passion

If you’re truly interested in the position you’re applying for, make sure the hiring manager knows it!

There’s a good chance the interviewer is going ask you why the company and position caught your eye, so think about your response to these questions:

• What first attracted you this company?
• What about the company’s mission/industry resonates with you?
• How does this position fit into your professional journey and your career aspirations?

If you have a friend, family member or professional contact already working at the company, call them up to find out why they’re passionate about their job.

3. You made a bad first impression

Potential employers are watching your body language very closely during an interview!

We’ve all heard that a weak handshake can give a bad first impression, which is true, but hiring managers say there are bigger mistakes:

1. Failing to make eye contact
2. Failing to smile
3. Playing with something on the table
4. Having bad posture
5. Fidgeting too much in their seat

In this YouTube video from Forbes, speech coach and author Chris Jahnke says job applicants often overlook the quality of their voice.

If you’re a fast talker, slow down and lower the tone of your voice to project confidence.

4. You had a bad attitude

Glassdoor’s experts say a negative attitude can be a deal-breaker, so you want to avoid saying anything bad about your current company or manager.

If you’ve been laid off, be prepared to answer the question “Why did you leave your job?”

When formulating your answer to this sensitive question, keep your explanation short and simple ‘ and remember to maintain a positive message throughout.

End on an upbeat note by letting the employer know that you’re excited about a new challenge.

5. You were too passive or too aggressive

To avoid coming across as too passive during an interview, jot down a list of questions to ask and bring a notebook to record the answers, Hichens recommends.

Also, be proactive and send a thank you email within 24 hours of the interview.

If being too passive isn’t your problem, being too aggressive might be. Nobody wants to hire a know-it-all. You want to come across as confident, not cocky.

Visit Glassdoor.com to learn about three additional job interview mistakes you’ll want to avoid.

More Clark.com jobs resources:

• This is the resume format most hiring managers want to see
• Help wanted: Employers desperately seek applicants for these 10 jobs
• 10 job interview mistakes you’ll most likely regret