Well I think that’s an absurd and extreme example, so the reductio ad absurdum is self-limiting, since serial killers are, hopefully, not the common case.

How about this analogy instead, being more in the realm of the applicable and commonplace: I broke up with many girlfriends, and had many short- and medium-term partners, before meeting my wife of over a decade now, who continues to knock my socks off to this day.

In practice, past performance is not a guide to future outcomes. How many times have we heard this caveat applied, in far more predictable markets than hiring and/or dating? Past performance of employment candidates is a subjective and observational assessment; relying upon it (especially in a negative framing) is to invite not only ones own biases to take center stage, but also those of others; see earlier point re. reinforcement of structural discrimination.

At most, someone’s past successes qualify them for my interview shortlist, but there are many other green flags besides, and I’ll save my type 2 errors for the back half of the hiring funnel, after assessing someone’s potential.

I'm not the person you're responding to, but I'm fairly certain that this was one of those so-called "jokes" you may have heard of.

Perhaps, but jokes can convey meaning, and I think this was the case.

[Dying is easy / Comedy is hard]

Man, I love Hyperion.

> whose previous 3 spouses died

Employment is not marriage.

Hiring someone who has hopped jobs 3 times is more like dating someone who has dated 3 other people before you.

And considering that, someone who has only held long stints at previous jobs probably gets a red flag for not being desirable enough to more companies or just plain lack of curiosity.