Things Sims Will or Won't do Autonomously

[Coocoo girl]

I know two things that I have caught them doing autonomonously, but that there isn't an interaction for it unless they happen to do it.  I had one sim "attempt to subdue"  the washing machine.  He did it and got a victory over washer moodlet or something silly like that, then there is look out window. 

Things sims will do so much that it just gets downright annoying:
Pet the cat.
read books.
play computer.
watch Tv.
Sprinklers

things sims will do so little that it gets annoying:
Clean!
Eat a meal after cooked.
Brush teeth
Make bed.   Sorry this was so long,  I just wanted to make the format look ok!Lol

[CynKuy]

Cats and dogs will hunt autonomously if they have high hunting skills.

[Magpie2012]

I actually have had my sim get her "first kiss" from another sim... I was a bit annoyed as she was getting all flirty with her IF only moments before and this other sim was definitely NOT her IF... She ended up with a "naughty reputation" from it too... I have also had my sims write, paint, play games/chess, read, listen to tabcasts (they seem to love logic and writing), clean, do laundry, swim/dive/lounge in the water, play with the sprinkler/water slide/hopscotch, repair sinks/showers/toilets, fish, flirt, teach toddler walk/talk, toddler will play with pegbox and xylophone and read autonomously, child/teen do homework immediately after school, to completion, cook, chat on the computer, stargaze, use the training dummy, break blocks (with enough martial arts skill points obviously lol), garden, play instruments, and using the athletic equipment... I'm sure some of this is trait related since my sims almost always have the genius trait, and lately in my personal legacy, with randomization of traits, neat/perfectionist/handy/family orientated/artistic... The things they won't do seems to be: sleep (I don't count passing out on the floor as sleep), eat (if they are doing something else they feel is more important), shower or pee... They do however look after their fun and social needs quite well all on their lonesome...

[Mahmeya]

Roommates in University town rarely take shower - it usually takes them at least one day of running around dirty.
Sims often turn stereo on (maybe they just want the free moodlet), and prefer do anything that gives loads of effortless fun.
Also, lot of actions are tied to their traits - my sims are usually obsessed with playing chess on computer, reading books or watching digital fish.

[Magpie2012]

And they always choose the most annoying radio stations lol AND leave the tv on... And they take stuff out the fridge to make food and then just leave the tray on the counter and walk off! And how impossible is it for some of them to flush the toilet?!? I mean really! It only takes like 2 seconds!

[Deklitch]

My sims love to use the deep fryer and ice cream maker autonomously. I ended up putting them in my locked kitchen in my dynasty house so that only my assigned cooking immortal and cooking mortals could access them.

My sims love to play chess. While on vacation, and I was concentrating on my logic immortal, my founder and gen 2 immortals decided to play chess together. thankfully I woke up the point when they both raised their logic skills to level 3. Then, I was trying to get my logic immortal to play chess against ranked opponents while on the same vacation. The ranked opponent in question was there when he was challenged, but both my immortal and his victim kept on trying to sit on the white. It seemed a loop they were in, so I reset them both, and tried again. My immortal won again.

Similar thing to that with the sculpting stations. I find sims decide they want to try their hand at sculpting, no matter how many times I tell them not to. They keep on returning for more, and I keep on telling them NO. I have a non-immortal who keeps on running outside and jumping on the trampoline. They also seem to be playing with the life goggles and/or computer games autonomously. I don't really have them playing foosball autonomously, however. They also don't seem to be attracted to either the chemistry or alchemy stations.

[Magpie2012]

Fairies and green-thumb sims are also more likely to autonomously go and talk to their plants for social interaction, in fact my one fairy refused to autonomously talk to her husband or her children but every 10 sim minutes she was on her way outside to chat with this or that plant :-s

[Esther1981]

Fairies and green-thumb sims are also more likely to autonomously go and talk to their plants for social interaction, in fact my one fairy refused to autonomously talk to her husband or her children but every 10 sim minutes she was on her way outside to chat with this or that plant :-s

No one understands like the plants! 

[Niana]

Adding to what Deklitch said - I've had witches and Supernatural Fan Sims autonomously learn alchemy

[Trip]

I've had sims without any traits or occult status pertaining to learning alchemy learn alchemy on their own. I stopped sending my human life states dynasty founder to the elixir shop for that reason.

[Deklitch]

oh wait, that's right, at the alchemy shop they will do that for me as well. However at home, none of them seem interested in it, apart from my witch spare whose job is to make alchemy potions.

[Turoskel]

I've had newlyweds autonomously be frisky, one couple in my dynasty who I recently married must have done that about 4 or 5 times during the two day period that they can, and they were elders, making up for lost time I guess as it was a first romance for both of them 

Before I put the sculpting station in a locked room I'd have artistic guests at my dynasty parties starting sculptures, thank god you can scrap them and it doesn't have to be the person who started it. I have also had some of the family autonomously go to make a potion on the chemistry table, not something you see often, I think they do it after they learn logic. Even so I keep that in a locked room as well now.

And a new one I've discovered, which I think is possibly more likely with certain traits, is streaking. I just did my first term at uni with my self sim and her other half Dallas, he's evil and the evil icon shows on streak, well he streaked when they came out the diner one night, and he did it again after nailing his finals, just left the building and promptly streaked around campus in celebration 

[rarespawn]

I've been working on an immortal dynasty (on generation 3), and I don't want my founder to gain skills in anything so I have her locked out of all rooms containing entertainment activities. 

The only things she has access to is a tv, and bookshelves.  I'm at the point where I kind of just let her do whatever she wants to do.

Which apparently is run through the sprinklers, non-stop, all day- every day!  She is supposed to be gardening (the reasoning behind the sprinklers in the first place), but everything but the trees have died!

[Magpie2012]

The only things she has access to is a tv

Be careful because she could learn other skills you don't want her to on the TV!

[Esther1981]

Adding onto what Magpie said, also watch the bookshelf. Make sure there is no skilling books in there or she could also learn a skill you don't want her too.