You can have your interview materials rehearsed and ready to blow them away, but it's the sound of your voice that could be holding you back.
Try recording yourself speaking, and check for these common habits of speech that are proven to undermine your words.
You might know this as "Valley girl" speak, but it’s creeping into Silicon Valley boys’ clubs, too.
"...you're making a statement but you're [also] asking indirectly for the interlocutor to confirm if they are with you," researcher Amalia Arvaniti told the BBC. It might become a cultural norm, but asking for constant affirmation when making statements sounds like a confidence problem.
You wouldn't show up to a job interview with bed head and slippers. Why sound like you just woke up?
Studies show that vocal fry—the creaking, drawn-out tone that emerges when speaking below your normal register—hurts first impressions of both men and women. Here are examples of normal and frying voices, compiled by the Atlantic from research published in PLOS One:
After listening to those examples, 800 study participants were asked for their impressions on which were more educated, competent, trustworthy, attractive, and appealing as a job candidate, according to the Atlantic. You guessed it: They preferred the normal voices by 83% to 86%.
Dr. Renee Gupta offers theories on why vocal fry happens:
The researchers in the Journal of Voice study observed that women were much more likely to exhibit fry than men. Earlier studies showed that this vocal creak was associated, in women, with being educated, urban-oriented and upwardly mobile. There’s a theory that because the rumbling, deep male voice is perceived as being authoritative, perhaps that is why women are emulating it. It may even be subconscious.
While you shouldn’t try to reach sizzling lows, having a shrill or soft voice affects your image as much.
In men and women, a lower voice correlates with higher positions of leadership, studies show. According to the Wall Street Journal, you want to be more James Earl Jones, less Gilbert Gottfried:
"...researchers found that executives with voices on the deeper (that is, lower-frequency) end of the scale earned, on average, $187,000 more in pay and led companies with $440 million more in assets."
Another study in PLOS One demonstrates our preferences toward low voices in leaders. From that 2012 study:
In hypothetical elections for two such positions, men and women listened to pairs of male and female voices that differed only in pitch, and were asked which of each pair they would vote for. As in previous studies, men and women preferred female candidates with masculine voices. Likewise, men preferred men with masculine voices. Women, however, did not discriminate between male voices.
Levo League addresses the issue with an example from their Office Hours with Sheryl Sandberg. Listen to Sandberg speak at TED: Her voice is confident and commanding the room, without straying outside of her natural tone:
Why are more masculine voices attributed to leadership positions, especially in women? "In the case of women’s voices, this bias could be a consequence of lower-pitched female voices being perceived as more competent, stronger, and more trustworthy," researchers say. It could also be a sign of maturity: As women age, their voice naturally dip lower, and more bass in your voice sounds like more experience and wisdom.
Soft or young-sounding voices aren't the only pitch-problem: Too-brash voices cross the line from self-assured to off-putting. "People may be tempted to say, 'Would you shut up?' But they dance around the issue because they don't want to hurt somebody's feelings," Phyllis Hartman, an Ingomar, Pennsylvania, human-resources consultant tells the WSJ.
Don't think your interviewer will miss that stray "ain't" or double-negative. On first impressions—when you're supposedly on your best behavior—grammar mistakes can be red flags for future performance. Solid reminders from Diane DiResta for Monster:
The interviewer may question your education when you use incorrect grammar or slang. Expressions such as "ain't" "she don't," "me and my friend" aren't appropriate. Be sure you speak in complete sentences and that tenses agree. The interview is not the venue for regional expressions or informality.
Slow down, calm your nerves, and think before you speak. A job interview is no place for regional dialects to slip in, even if it is a casual environment. If you know there are tricky industry words or names you'll need to pronounce, practice them first.
If you're still feeling unsure, this video from mental_floss crash-course corrects 38 common grammar and usage mistakes: