Among HR consultant Stefanie Fackrell's red flags in a job interview is a lack of preparedness. Fackrell has worked in recruiting at tech giants like Google and Nvidia and has always noticed when people come in not knowing anything about the company or the role they're interviewing for.

"You can tell when people are just phoning it in," she says. And it makes it hard to believe they're going to be invested in the role or perhaps that they're interested in it all.

In fact, when it comes to the worst interview she's ever seen, the interviewee told her directly just how uninterested she was. It immediately made Fackrell think, "maybe you shouldn't be interviewing …" Here's what happened.

'Oh, it's not my first choice'

Several years back, when Fackrell was interviewing for a recruiting coordinator to join her team, a young woman came in to be considered.

Early on in the interview process, Fackrell asked, "so what makes you interested in this role?"

And the woman replied, "Oh, it's not my first choice," says Fackrell. "I'm waiting for a potential offer from this other place." The woman admitted she was only there to see what the interview experience was going to be like and what she could get out of it.

Fackrell knew immediately this woman wasn't a good candidate, but she carried on, let her colleagues interview the woman as well and simply put in her feedback to the team that she didn't think they should hire her.

'So many people are out of work'

Especially right now, when it comes to applying, "I think so many people are out of work that they're kind of throwing everything against the wall," says Fackrell. "Roles that may be too junior for them or something that they're not really interested in." But this can be a bad approach.

The interview process is intensive and multifaceted. "It's preferred to not waste anybody's time or resources," yours included, she says. Instead of letting your prospective employer continue to dedicate time to your candidacy, as soon as you know you're not interested, shoot the recruiter an email and say, "I will not be moving forward with this opportunity."

When it comes to Fackrell's candidate, "my No. 1 thought is if we hire her and this other opportunity comes through, she'll be gone in two weeks," she says. Even if the woman was somewhat interested, she spoiled her chances by saying she wasn't and continuing to use up the team's time.

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