I always put pillows on the floor if my baby is on the bed or on the couch so if he does fall it will not be directly on the floor.
my advice is to put baby on a mattress or with a cushion on the floor. if you are doing work and you do not see baby and that could be the safest way to keep baby safe.
My pediatrician told me it happened to her! Probably is much more common than you would think. And I seriously doubt anyone that takes their baby’s picture daily is a bad mum. 