My DSS is the same, and I just don't understand it - but that's just because I was the complete opposite as a teenager.
We no longer allow him to eat upstairs because he doesn't bring the plates down, but even so he somehow ends up with plenty up there - I don't actually know when he's getting it, but I have a suspicion he comes downstairs for food at night after we're in bed.
It's the washing that does my head in the most.
I have tried asking him to do his own washing. I do all of our washing once a week on a Saturday, and get everything washed and dried. When he has been asked to do his washing, you can guarantee he'll have put it in the wash and then done nothing about it. So it will have sat there for days, and obviously there's a smell to it then. So I have to put it through the wash again and then dry it, and THEN do our washing. He's at his mum's at the weekends so it's either that or don't do our washing. Asking him to do his own actually makes it harder for me.
He's the same in that he's too lazy to put clothes away, so he'll just dump them somewhere, and then the clean ones will end up back in the wash. You can tell if a t shirt has been worn by a sweaty teen or not.
It's towels that do my fucking head in the most, though. To be fair, he does shower quite a lot for a teenage boy, so that's good. BUT, he will take a new towel every single time, but they just build up on his floor and he doesn't put them in the wash. So then I end up having to go round his shithole of a room to find the towels to wash them, or else we don't have any to use. I've told him he's not allowed to take a new towel unless the other one is in the wash - he says okay, but it's ignored. I've then bought some grey towels (our others are all black) and said that those three are the only ones he's allowed to use, and if he runs out because he's not done his washing then that's tough - again, he says okay but just takes ours when it comes to it. I've even tried storing them in our room instead of in the bathroom, but again - he will just go and help himself.
I know if you're parents of teens you'll probably think I'm being dramatic but I think it's just because I've been thrown in at teenage level without having the slow build up and progression from a child (and without having the unconditional love a parent would have) and the messiness, selfishness, laziness and thoughtlessness actually makes me want to move out sometimes.
DP has been working absolutely ridiculous hours since the start of covid so it's me here when these things have to be dealt with, DP does his absolute best but there's nothing we can do about the fact that it's me here all day and not him - and then DSS goes to his mum's before DP comes home on a Friday so no chance for a chat even then.
I can't take it anymore.