Beyond the fire risks mentioned by others, front loading washers and dryers are sometimes used as a hiding place by children which has led to serious injury and deaths
How many kids hide in ovens? They're all front load and you routinely turn them on without putting anything in.
Also, you’d usual need to take the rack(s) out of an oven for a child to get in.
You will literally have to smash the front glass window (which is at least two layers thick) in order to pull your drowning child out across the broken shards of glass, or have a prybar handy.
This might sound like an imaginary scenario, but it's not at all. It happens every year, and no agency has stepped up to mandate "An big red emergency unlock manual handle seems like a good idea, even if the water pours all over the floor", even though we have mandated emergency trunk pulls from inside vehicles (another place where kids like to hide.)
https://www.google.com/search?q=child+dies+front+load+washin...