The first time I interviewed (and failed) with Microsoft, the final stage of the interview was with a guy who had been with Microsoft for 20+ years. He looked at my resume and grilled me about job hopping (even asking me about individual positions and why I left).
Ironically, I didn't even job hop just for salary, I did it because of layoffs or really toxic environments. However, all that job hopping was also crucial to gain different experiences I have today in different technologies, patterns, and sets of scale I would have never gotten in my original company.
While explaining this to the interviewer, he started talking about how he started in the operating systems division, then moved to security, then moved to office, now works in an Azure area. He failed to really understand that he was doing the equivalent of job hopping in order to facilitate his own technical growth, and the majority of us do not work in companies where we are able to side-load into vastly different domains without changing high level companies or losing RSUs.
I don't think this was the reason I failed the interview (I didn't interview well that time), but I do think about that.
As for senior roles, you have your data backwards. Senior roles have higher turnover, including in Switzerland. They're paid more, but there is also much more risk associated with the roles. They're some of the first roles to go during strategic and structural shifts.
Conservative is the name of the game here, and its not specific to banking, whole society runs like that and you would struggle to find a company behaving differently, mostly just startups.
They simply prefer stability over bleeding edge, and job hoppers are anything but stability, that's obvious from a light year away to anybody with any experience. In fact it signals a person who is often not happy and instead of improving things they just move - one of the trademarks of juniors with big egos.
Also hiring on a perm position takes time and effort (and costs a lot), nobody is eager to waste so much resources again and again just to have potentially slightly more efficient employee.
I've been on the other side and agree with arguments generally, but this is generally their way here and they are doing just fine.
Where I'm from (Norway), job hopping every year or every two years, would look real bad. Software Engineering IS a bit more forgiving, but you're still going to get asked "why have you switched jobs five times, since you graduated in 2017?".
In fact, there's a real chance you wouldn't even land an interview. The employer is going to assume one or more of the following things
A) The person gets easily bored, and constantly needs fresh and stimulating work.
B) The person does not (easily) get along with people, or has problems with settling at a workplace.
C) The person is constantly being let go / can't hold a job.
D) The person is very salary/compensation focused, and will jump ship on the first chance.
Hopefully some of these things will be uncovered when contacting references - but there are lots and lots of former employers that will cover up for a bad hire, just to be polite. Or the bad hire is very good at picking people to use as a reference.
So you're kind of stuck with a candidate that's either job hopping because they want to "level up" as far as salary goes, or some other underlying reason they can't stay.
If tenure over 1-2 years is of no importance, then that's obviously not a big deal. There are businesses, ranging from startups to mega corps, that just need warm bodies to power the various projects - easy come, easy go. Be productive from day 1, and work them as much as they can.
But for highly specialized firms and positions, where you spend the first N years on training, job-hopping candidates could be completely unacceptable.
In the US, no one has ever asked me why I never make it 2 years at a job. I recently got a new job that gave me a senior title and 50% increase in salary.
Oh no, someone in a design and problem-solving role need stimulation!
I get what you're saying, but the idea that this is a negative really stings.
You have on your otherwise amazing CV job switch every year or two? Well we won't even meet since such a person wouldn't be a match for our bank, as for the rest of banks. And most other industries. When employer is choosing from pool of 100-500 often good candidates (since smarter half of the world strives to get here), this is more then enough to dismiss a candidate.
I get it, I've done it in the past (elsewhere) too and its true you get higher base salary. That's the end of benefits. People who are in only to start things, not to maintain/evolve or even deliver final product are largely not interesting to stable companies. its not a rocket science neither, everybody is aware of this. And its not some automated skill all people magically have, in contrary - some of the brightest folks I've met would fail exactly at this check.
And the more senior the role the worse it looks. In fact ie some department leader switching jobs every 2 years means something is very NOK.
Off to body shop consultancies, that's a perfect match from customer point of view. Use them for 6-12 months and them move on.