I do set a timer on my watch according to what the machine estimates: 59 minutes for a standard wash and 1:15 for a standard dry. Sometimes the estimate is off, so it’s not perfect.
Then again, why do I have to remember to have my phone or watch in order to use the laundry?
An actual notification could be better because I don’t have to have my phone nor remember to do it. Sort of like in the olden days when the machines had that god awful buzzer you could hear throughout the house: it just worked at least if you’re home. Now the machines let out a pleasant little tinkle that I can’t hear from the living room, plus what if I want to be outside.