Lisa Barrow discusses with Business News Daily what not to do after an interview.  

https://www.businessnewsdaily.com/8364-post-interview-mistakes.html  

Here are some additional thoughts…

Bringing forward competing offers after the interviews have all commenced can be a big mistake for otherwise promising candidates.  It's important to be transparent throughout the process of where you are in the interview phases with other companies.  

Candidates who bring information out of left-field in the eleventh hour can come across to their potential future employer as disinterested or it may feel to the employer that the candidate is just using them to leverage a better offer somewhere else.  If there is a competing offer that comes in after the fact, let the company know right away and also let them know where they stand.  Just as poor of a mistake is to take the other offer without letting the other company know beforehand so that they could potentially counter.  

In the case where there are multiple people that are up for the same position, this can definitely sway a hiring manager toward another candidate.  Even if the candidate is the only one up for the role it can leave uneasiness with the employer that could ultimately lead them into bringing other applicants into the fold, adding additional competition for the position.  

To avoid this pitfall, candidates should be as transparent as possible on where they are in their job search activity. They don't have to tell them about every application you have out there, but if they're in late stage interviews or offers somewhere else, let the company know.  Honesty is always the best policy.  

If a candidate goes through the interview process and doesn't mention other places that they are considering but then get a competing offer, all is not lost.  If they have to let the company know after the fact, they need to be sure to let them know how interested they are in their position and any relevant factors that will help them weigh out their options.  It is important for the candidate to choose their wording wisely though, and not to come across as too threatening.

I had a candidate go through two rounds of phone screens and a day-long interview at an ad agency in NYC for an Account Supervisor role. She said to me that she wasn't actively interviewing anywhere else.  She was absolutely thrilled by the opportunity to work at this company and anxious for the offer.  After the interview, she sent a thank you email to the CEO that also included a mention to an offer at another agency she was considering, but stating this was her preferred role. The CEO called me up to say that he was a bit taken aback and concerned in her lack of transparency in the process.  He felt that it was a veiled attempt to hold his feet to the fire on a time-frame and as a negotiation tactic. Following further discussion, it turned out that she really wasn't considering the other offer and she had only mentioned to show her high level of interest for this particular agency.  She apologized and ended up getting (and taking) the offer, but this ultimately showcased the importance of transparency and the impact it can have in the process.

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