So, I've been playing a lot with Elders now and I never had one of my Elders roll the want to retire, but I know that they indeed can roll the want to retire because Olive Specter and Consort Capp have this want at the beginning of the game. Now does anyone know HOW this want is triggered or when they usually roll this want?

And besides that does anyone of you has a specific rule for your Sims to retire like immediately when they aged up or after they have lived a specific number of days or when they rolled the want for it?
I usually let them retire 10 days after they aged up.

I mostly see it immediately after the elder birthday.

I don't know, but I would think Fortune Sims would be less likely to want to retire, while lazy or playful Sims would be more likely. I rarely see it, though, as mine generally retire immediately they age up, unless they have some paid vacation left or are sure to get a promotion if they go to work one more time.

I haven't had that many pixels retire, but my rule is going to be pretty flexible-if they've reached the top of their career or they're never going to reach the top due to laziness/incompetence. You can always lock that want, too. Which is what I do.

looking at the BHAVs of a Want (in SimPE) might give some idea of when the Want is triggered; or might at least tell which characters could have it.
within Pie Menu Functions and/or Object Functions, such BHAVs would be "Guardian" BHAVs.

Having a grandchild often triggers it and they don't need to be elders, a few of my adult sims with grandchildren have rolled the want.

The few Elders I have I made it my business to make them "Platinum" after retirement, I find they seen to be much happier.
Like Old Goth in Pleasantview who already was retire in the game he was not happy until I made him max out all skills, to become Platinum being that he was already a knowledge Sims he love learning.
I use a mod to change his life time want and my other Elderly Sims, so they are all retire getting their pension and happy and Platinum they live their life meeting and having tea.

My Fortune Sims get the want to retire and as soon as they do they get 3-4 wants for another job.

Well, thankfully once they do retire, they can take on a part-time job in order to fulfill those wants for another job..

One of my adult family sims wants to quit his job since having 4 children (1 child, 1 toddler and twin babies). Thank you, ACR! But for elders, I usually see the retire want right after they age up.

I know from the code that one possible trigger is having a grandchild (without any checks for age), and it will trigger again if the grandchild ages to toddler or child. It's more likely for nice sims and family sims.

I've raised the retirement age in my hoods (Lol/omg) because so many of my elders have families who need that spare income. Many teach, since they're safe from adding kids to their classes, but many are also parents who still have young children (teen or younger) at home. A number own businesses, another portion provide live-in care for grandchildren, and a few more adopt stray townie teens and provide them with stable homes. A very small subset have made their money, launched their dependents, and have enough home comforts to retire and live on their pensions. That said, I do see the want to retire come up every now and then. Breaks my heart to ignore it... it really does!