In my personal experience, clothes start smelling funky and 'off' after about 3 hours wet after a wash, and the smell persists even after drying. Only solution is to rewash the entire load.

Also, if you have a front loader, they are extremely prone to growing mildew in the bottom of the rubber gasket. Leaving wet clothes inside makes that much more likely.

Is it very warm where you are located? Here in the UK I can sometimes forget washing over night, or 24 hours in the machine (front loader) and not get a problem with smell, any longer and I likely will - and don't worry my wife tells me when it smells off! Never had a problem with mildew in the gasket either - maybe too cold here? Or maybe the weekly hot wash i do keeps the machine clean?

Same here in Melbourne (au), have forgotten clothes in front loader for 24 hours sometimes, and they've been fine. I guess it's either climate, or front loader, or appliance hygiene. Or a combination thereof

I find this depends a lot on where you are. In my house in California, I can leave the clothes in the washer a lot longer. In florida, the washer is already stinking most of the time. Even if I disinfect the washer occasionally with bleach, it still ends up stinking again. I put this down to the general humid environment.

Do you close the door on the washer? We have front loading washer and leave the door slightly ajar. When it's completely sealed the darkness and humidity are a breeding ground for mold.

Could be the water quality as well.

Florida water stinks like a swamp right out of the tap.

White vinegar in the prewash will kill the mildew smell.

White vinegar can also help when washing clothes that tend to bleed color (e.g. Just-bought dark blue jeans). Wash these once with white vinegar and the color should "stabilize".

I buy that stuff by the gallon. If you live in a high humidity area it has so many uses.

If a washing machine waits up to say 30 minutes unless you click the fast button, that's still quite a bit of time shifting in aggregate. Same for home heating/cooling, you might be willing to shift an extra 1-2 degrees if it will save a few dollars a month and you don't need to pay attention. However, if your willing to spend a few extra dollars a month that directly pays for grid storage.

Yes. This only matters for half an hour, once a year, when there isn't enough wind or sunlight to generate electricity. It's OK for a washer to just say no if you try to switch it on in that half hour, and maybe that makes more sense than buying a large battery that only gets used once a year. The timing can be forecast, and the news would warn you the night before.

The US grid already has a lot of storage in hydropower systems. So, I doubt a washing machine would ever need to say no.

Further the once a year useage is going to be drawing a lot of batteries slightly lower at the cost of slightly shorter lifespans not a single bank that's only used once. Plus some emergency back up generators that flip on and use some minimal amount of fuel at hospitals and data centers etc.

PS: One interesting outgrowth from high wind solar production is likely to be fairly accurate models for electricity costs over the next few hours. So, you may be using power sooner if the prediction is a coming price increase.

You need to bleach your washing machine if clothes are getting funky after three hours.