Older homes, adapted laundry spaces
Many properties here predate the standard purpose-built laundry room. Machines end up in garages, converted utility spaces and back rooms, sometimes on concrete that is not perfectly flat and often with plumbing that has been extended to reach them.
That context matters. A long drain hose run, a standpipe at an awkward height or a machine sitting slightly out of level all produce symptoms that look like machine faults but are not.