One issue is jobs are generally all or nothing. An equivalent pay cut for an extra 4 weeks off a year is appealing. But, most companies hate the idea of someone working 10 months a year vs 11 months a year.
Well, all the simple jobs that you can drop into and out of like that are being automated, so competition for the remaining jobs is fierce and accordingly pay and conditions are terrible. The remaining jobs are all, to some degree, knowledge jobs, and there are significant sunk costs in bringing each employee up to speed. Would you rather spend $50-$100k (minimum) to train one full time employee, or $100-200k to train two part-time employees to cover that same role?
I can’t think of any company that pays for that kind of training. Due to frequent job hopping company specific on boarding costs are generally kept fairly low.
More widely people truly work alone, companies need redundancy in the case of illness, vaction, or other such matters. Further, their is a benifit to be able to staff a team with a non integer number of people without splitting focus across multiple projects.
I'm not talking about formal training, I'm just talking about the fact that when you take on an employee in a knowledge job, it's usually quite some time before they start contributing positively, let alone reach their potential. In software, generally it seems to be around 6 months before a new player is a full member of the team, and the first 3 months of that they're a net negative because they're taking up more team time asking questions than they're saving by doing work.
3 months at say -10% productivity and 3 months at say 50% productivity does not add up to 100+k for most employees.
On top of that, new people really should be a net gain by week 3-4. It’s not about what they get done but the time they save other people. Inexperienced people may take longer to get up to speed, but they also cost less.
