There’s a spread in performance from the +1σ to the -1σ nurse, but both will be functional in a nursing role, so checking credentials is a mostly sufficient evaluation of occupational ability.
The spread in software ability is so much larger that the -1σ candidates (the least-effective ~15% of people who have ever worked in computer programming jobs) are worth trying to select against in a way the least effective ~15% of nurses probably are not. (I’m not in medicine so I’m not sure; apologies if the same effect is at play there as well.)
This isn’t an argument against credentialling since it is literally the direct effect of not having credentialling in software. Credentialing cuts most-to-all of what would be the low tail of the profession off before it ever enters. Nurses and lawyers who can’t do their profession’s equivalent of fizzbuzz mostly wash out of the exams to enter the profession (or earlier), they don’t show up in job interviews, except where the inability is produced by some kind of post-entry decline in capacity. And even then, decertification is a real possibility, which further purges the low end of the distribution.
So, yeah, a -1σ software developer (or at least software developer job applicant) is worse compared to basic expectations than a -1σ nurse, because a nurse as below expectations as a -1σ software developer is would be compelled to find a different profession because of credentialling requirements.
You can only be so much better at nursing than the average qualified nurse. How many more patients will the best nurse save? You can be several multiples (whether it’s 10 or not, I won’t get into here, but I think it’s at least 3) more effective than the average in SWE.
I...disagree rather strongly that this, to the extent it is true, differentiates SWE from nursing. Comparing workers with identical responsibilities, the same is true in SWE, in both cases there are large impact multiples possible within the field, but they come from roles with greater responsibility; in nursing, because different roles require different credentials, this is reflected in the fact that a more competent nurse will be more likely to take on a more responsible role within the same credentialed category, and also be more likely to acquire greater credentials over time compared to a less competent nurse. “Nursing” isn’t a binary credential, but a whole set, starting with a basically heirarchical set: CNA -> LVN/LPN -> RN and beyond that various Advanced Practice Nursing credentials.
SWEs likewise have wide variety of scopes of practice and responsibility, but because we have no structure in the profession, they are assigned ad hoc and even with common titles there isn’t consistency in substantive roles, skills, or qualification. But, again, that’s a product of the absence of structure and credentialling, not an argument for it.
Whatever the highest-level credential is, SWEs will have a spread that’s wider than the highest-level nursing credential (and likely wider than the ratio in the entry-level SWE range as well).
I see, and you have presented, no reason whatsoever to believe that this is true.
By comparison, given the physical and time constraints of the job, an excellent nurse might be able to spread their expertise to 2x as many patients as a median? 3x? I think even 3x is a stretch. Maybe they can make a life-saving catch in the hardest 5% of cases (definitionally, very rare opportunity to apply this level of skill)?
This is why a top PI or scientist can literally save hundreds of millions (as Norman Borlaug did) but the best surgeon can save mere thousands in their life at best using surgery¹. There is a scale effect.
Likewise, SWEs can write code that can apply to all people.
Same with the top public policy people, for instance. It's the length of the lever and where the fulcrum is placed.
No nurse has that lever.
¹ I hate having to handle the edge-casers, but scientists can come up with new surgical procedures (as Werner Forssmann did) and that is way for them to use a long lever.
(Jon would have started with entry-level credentials at some point.) Substitute with Dennis Ritchie, Linus Torvalds, Bjarne S, Peter Norvig, James Gosling, Brenden Eich, rtm, rms, or whomever your idea of someone obviously on the right tail of the distribution is.
I'm sure there are famous and outstandingly accomplished nurses, just as there as there are for SWEs. My claim is that there are likely more of the latter and more continuous distribution of them.
Many many different industries have jobs that require technical skills -- not tech as in technolgy -- and they get away just fine with managing to hire people. Nurses need to be able to nurse, a highly technical skillset; no one is having nurses give fake shots on test dummies during interviews. They use credentials and experience, and accept the risk that a hire might not pan out.
The fact that we want senior level developers to have to refresh/cram before interviews on how to implement graph search algs and hash tables just so they can pass some artificial whiteboarding section is a bit crazy. Their actual job experience over the past N years should be what counts.
Now, conversations about how one would solve technical problems of a sort actually faced on the job are totally on point, and really should be a part of any job interview in any field.
edit: Really, what we want as engineering types is for there to exist a way to gauge ability in a purely objective way. But there isn't one; it doesn't exist. Furthermore, you are building a team of people. IMO the focus should really be on fit and soft skills regardless. Make sure they meet a minimum bar of technical ability, then work to verify whether they'll be a productive, beneficial teammate.