I used to do the washing for the whole household, with the rule of if it's in the basket it gets washed, if it's left on your bedroom floor, I ain't coming in there to pick it up (I have a now-18yo stepson, so no thanks!)
The problem is, me and DP would just put our washing in the basket as and when it needed doing, but stepson would wait until his room was absolutely full of dirty washing, and THEN put it in the basket, meaning it was so full it couldn't even close.
I said the next time he did that, he would be doing it himself. He did it again at 16, so he's done it himself since then, and has his own washing basket in his bedroom.
Sorry, but I have enough to do, and enough washing as it is, without him then dumping an absolute load of washing in the basket (usually announcing that he needs x, y or z for the next day for good measure).
It's all very well washing for your teens if they're otherwise helpful, or at least thoughtful/civil, but in my case he's made it very clear that he doesn't respect me or this household, and I'm nobody's mug. So there we go.