I think "fit" is a cop-out when left unspecified. It's a reasonable way to reject someone when you can clarify why someone is unfit. I think rejecting a hire because you don't like them isn't okay unless you understand why you don't like them.
Understanding that someone would be bad because they're overly argumentative, can't take criticism in a calm or level-headed manner, or because they're prone to interpersonal conflict is a legitimate way to reach the conclusion that they would be a bad fit. But if you get the cabal together and accept a simple "I don't like them" without requiring details, it becomes ripe for abuse; if only by your own subconscious judgements.
I used a simple hypothetical example around one desired trait, but I hope you understand how hopeless it is to have an objective standard for "fit/unfit" when it changes according to the dynamics of the team.
A boss of mine many years ago gave me the advice, "To be successful as a leader, you have to remember that your primary task is managing personalities."
Generally managers chose whatever course of action makes their own lives easier; and will then convince themselves that that's also in the interest of the company. The research the article cites should make it harder for HR managers to do that in the future; but we'll see.
If nothing else, this research gives you a way to evaluate your HR people. If they aren't hiring a variety of personalities, or are predominantly hiring people with personality scores very similar to their own; toss them immediately.
I'm happier in teams where people try to promote people and work due to some shared understanding of merit, but realise that a lot of success in a group is due to its member's preferences and behaviours, and not to any objective measure of value. People should be able to concentrate on doing what they consider to be quality work, without getting depressed over not being seen as 'objectively good'.
But that semantic issue aside, I agree with your point but would take it a step further. I chafe a bit even at the idea of "shared understanding of merit". Not that there aren't objective differences in performance, but that they vary across roles, and even within a specific type of job, different employees may have wildly different yet equally successful approaches.
I've come to believe the concept of A, B, and C players to be fundamentally flawed. The truth is that people perform differently in different situations. If you are hiring for a major brand-name corporation you obviously need some aggressive filtering to get through all the applicants, so I don't really fault the Googles and Facebooks of the world for their hiring approach. But I have always had success by shaping roles around the employee's strengths in practice, not based on some abstract ideal I'm searching for. Many of my best hires have come from unfamiliar backgrounds which I could not evaluate objectively, but whose diverse experience ended up paying huge dividends to the entire team.
They're toxic IMO and the best strategy seems to be making sure they're not on your critical path. Tech companies are often allergic to admitting that personality can be disqualifying on its own, so actually laying these toxic folks off can be borderline impossible before their behavior explicitly endangers a co-worker physically (e.g. Doxxing on 4chan).
Yes, these folks get outreach from sympathetic peers constantly, but it never seems to take.
While I wouldn't want to work with people with toxic personalities (and they do exist and can be hugely destructive) but I wouldn't want to equate someone being a bit shy and not in your face with their "personality" with being "toxic".
What are the goals for this new hire? Why is someone being hired?
Scenario: A team isn't performing optimally. They are making bad or non-optimal decisions. Work isn't being done well or on time.
Do you hire someone that will "fit" so everyone can continue to drink the Kool-Aid and nothing changes? Or do you hire someone with less "fit", with the aim being to shake things up and correct the path forward?
In this case either you fire people from the team and, Grizzwald style, proclaim "We are going to do a good job dammit!" or introduce an agent of change in the form of someone with a different (or greater) experience base that will, with your input and support, help correct the situation.
This "fit" thing can very easily turn into an echo chamber. And that is rarely, if ever, good in any way.
Every good team I've ever been a part of (or hired, once running my own business) has had various degrees of conflict or "un-fit" individuals. I find this works well.
If the narcissism of small differences wasn't a thing, I might agree.
Personalities and skills impact a given team's success. Pretty sure this was already obvious. What is not addressed in this article is the implications of this. It might not be very PC to research or discuss how personality matters.
But if skills alone are not enough when hiring, then one implication is team's can't really hire blind - they will have to get into personality as part of the interview. I have seen people push for more blind hiring practices, that is to focus on grades, experience and skills and downplay personality or other character traits - but this doesn't appear to be a competitive solution. That also means all the workplace studies that don't include personality when comparing success in the workplace will not be telling the full story. Sorry I have no solutions, but I do see hiring based on personality or "fit" remaining a target even when it makes sense and is done appropriately and the right intentions.