Get To Work: With Suzy Welch

Suzy Welch: The 5 biggest interview killers to make sure you avoid

How you perform in an interview can make or break your chances of getting hired. But it's not just how you answer the questions — your language, attitude and the way you carry yourself are also under scrutiny.

Professional networking site LinkedIn recently conducted a survey that asked hiring managers, "What actions, traits or behaviors would make you disqualify a candidate?"

Using results from the survey, bestselling management author and CNBC contributor Suzy Welch breaks down the five interview killers that can instantly hurt your chances of landing the job:

Bestselling management author and CNBC contributor Suzy Welch.
Bestselling management author and CNBC contributor Suzy Welch.

1. Inappropriate attire

How you dress is the first thing hiring managers notice before you even open your mouth to answer a question. For this reason, 60 percent of those surveyed say they would disqualify a candidate who is not dressed properly.

"Look, these days, it's perfectly OK to show up in jeans and a t-shirt if, and only if, you're interviewing for a tech company with three employees who think hoodies are formalwear," Welch tells CNBC Make It.

Outside of that, she says candidates should be very careful to make sure their attire fits the company they are interviewing for.

"Your interview outfit is a signal that you're aware of the company's culture and — just as important — that you understand the power dynamic of the hiring situation," adds Welch. "They are the buyer. You are the seller."

When in doubt, she says it's always better to be overdressed than underdressed.

2. Being late

According to Welch, being late to an interview is an immediate red flag that says to hiring managers, "I'm a screw-up."

"My rule of thumb is make sure you're saying hello to the receptionist 10 minutes before your set meeting time," she says.

If your interview is in an unfamiliar part of town, it may not hurt to also do a drive-by the day before to make sure you understand the parking situation and the route you need to take. Unexpected delays such as tough parking and confusing turns can easily throw off your planned arrival time.

3. Bashing your current employer

Regardless of how horrible your current boss may be, results from the LinkedIn survey showed that hiring managers frowned upon candidates who bad-mouthed their current or former employer.

"Saying things like, 'My boss is a jerk' or 'My company has terrible products,' broadcasts your indiscretion and immaturity," says Welch.

Yes, you may have to explain why you're looking for another job, but Welch says it's always best to respond with an answer that shows your desire to grow and have an impact in a new role.

4. Humble bragging

There is a fine line between discussing an accomplishment as it relates to the job, and boasting about an accomplishment simply because it's impressive.

For example, Welch says if you were a valedictorian at Yale, the way you mention it is not by saying, "My parents still can't figure out how I graduated first in my class from Yale."

Instead, she says you should discuss your academic achievement as it relates to the job. If there is no correlation between the two, then don't mention it at all, and simply include it on your resume. Hiring managers will still be impressed by seeing your accomplishment on paper.

5. Using your cell phone

An audible cell phone notification will break your connection with the interviewer — and indicate that you're not 100 percent focused.

To avoid embarrassing interruptions from a ringtone or message alert, Welch says you should always turn your phone off or put it on airplane mode before an interview. If you don't, she says you can easily be "seen as a person who's got their priorities all wrong."

Don't make the interview process any more challenging than it already is. "Avoid these instant interview killers like your career depends on it," says Welch. "It does."

Suzy Welch is the co-founder of the Jack Welch Management Institute and a noted business journalist, TV commentator and public speaker.

Video by Richard Washington

Like this story? Like CNBC Make It on Facebook!

More from Suzy Welch:

How to deal with a nightmare co-worker

Here's the exact right way to ask for a raise

How to answer the interview question, 'Why are you leaving your current job?'