I've absolutely done it before because I'm weird. Entering 1:90 (on my Kenmore microwave) ticks down 1:89... 1:88... etc. until it hits 1:00 at which point it will continue as normal to 0:59.
1:60 behaves similarly.
I have a feeling the "add 30 seconds" button will correct it to proper time format, but I'll test it for science.
My microwave won't start with just the add 30 seconds button. Others that I've used work that way, but not this one. So 9-9-start would work for me, while add 30 3 times would not.
On mine, you can only add 30 seconds, if you started it with that button. If you start the microwave any other way, the "+30 sec" button does nothing. It's annoying.
So if I'm reheating something on power level 7 or 8 (or even cooking popcorn with the popcorn button), I can't just add 30 seconds. I have to let it end and then start it up again.
Yeah dude... If you're reheating leftovers on full blast, you've been making everything worse. Microwaves aren't perfect, but you can def finesse it a bit, and it makes a huge difference.
Try doing 80% for reheating. Also, stir occasionally (for stirrable foods), and pause to rotate the plate occasionally as well. Even if it's already on a carousel.
Oh wow I find that so interesting - basically it's up to the manufacturer to decide what "add 30 seconds" means and so everyone does something different, it would seem.
Tbh I think I would prefer your way, bc I far more often want to do merely 30, 60, or 90 seconds total (so just 1-3 presses of that button 🔘), whereas I virtually never want to change the timing of something after I've already started it. It probably depends heavily what task it's being used for - rewarming a drink, 90s tiny popcorn bag, 30s quick warming of food after it cooled, etc., and more importantly how routinely the task is performed.
And for that reason it would be cool if they could be reprogrammed:-). Linux has spoiled us all far too much:-).