Why not give unpaid leaves?

A couple of reasons come to mind:

1. Your employer should be making more money off your work than they pay you. This means that they are worse off if they employ you less often. The reduced output will hurt them more than the reduced salary will help.

2. The business keeps going when you are gone. If you are a tech worker, part of your value is the ongoing development and maintenance of systems, or more generally your handling of some issues. This work has to be transferred while you are gone, which is disruptive. It’s like the switching cost of hiring and training, which your employer would prefer to avoid. Other commenters bring up consulting, where this can be clearly defined as not your job.

3. Although it’s a valuable benefit that could help attract talent, it could also select for less committed candidates. Asking for this in a negotiation suggests you don’t really want to be there.

Maybe one day, but it involves changing the entire system. Example: I’ve been an attorney for a decade, have paid off my debt, have a very manageable mortgage and rental income, and could easily take a 40% paycut to work fewer hours. I would love to do this. I could not have done this 10 years ago though when I started practice - I had too much debt, rented a condo, and had no assets to speak of. So employers are in a bind because filling part-time positions can be difficult as most people entering the professional labor market for the first time need full-time work because of the debt required to get there. So if I get to work part-time now, once I leave my office my employer would struggle to fill my job. Tech is a little a different, maybe, but most people that start a family and buy a home want/need at least one person working 40+ hours/wk to pay the bills and get insurance (another poorly managed but intertwined issue). Also, even considering this proposition is truly a luxury that only a tiny fraction of the population has. Which doesn’t add to the conversation, but I find it depressing.

I know lots of people who do this. They are contract labor (or consultants if you prefer that term). The contract is negotiated before work begins. Many employers like to make the initial term short so they can terminate the folks that don't work out. Most US states have "at will" employment laws so either party can terminate at any time.

The drawback is of course that you will have no job stability/security, and no benefits (unless you go with a big body shop).

If you have the skills and reputation, employers will want you on your terms.

I had a friend who took 4-5 months off unpaid leave every year at our large enterprise tech company. He had no dependents and was sufficiently independently wealthy that he didn't particularly care if HR threw a fit and didn't want him back. But he always came back, no issues.

I always wanted to do the same but I needed the income so didn't dare try. Which is exactly how the companies want it.

Screw taking 4 months off, I'd take every Monday and Friday off for the 40% pay cut any day.

No one will offer me that job though.

Because...

https://news.ycombinator.com/item?id=24077391

Google allows 3 months of unpaid leave at request.

Anecdotally, I've heard companies that tried this (something like 3 months unpaid after 5 years tenure) found that most of the employees who take this end up leaving soon after coming back.

Because healthcare is tied to your employment 35 hours a week in the US.

In other countries, similar laws trap employees into necessarily working even if they could do the job part year.

Perhaps this would work for some people, but the majority of people don't have the luxury of living life without responsibilities. If everyone took long breaks, companies would be stuck in a cycle of handovers and making sure that certain people aren't given anything important before their long break. If you want that kind of lifestyle it may be a good idea to look into part time consulting.

Because work and life doesn’t revolve around your schedule?

If you are entrepreneur, it just gets worse unless you are the ~5-10% of the super successful ones

Most Teachers get summers off