It's not really all the washing and cleaning that they do, but the fact thay they do all that and the minute they put lotion on, the baby will poop. Or spill something. Or create a mess. Or insist on being fed.
Basically, it's a law of nature and the degree of mess requiring the use of the mothers' hands again will be directly proportionate to how expensive the lotion or cream she just lathered on.
And yes, of course, after washing baby's tush and setting things right again, she'd forget to put lotion again.
And yes, she could wear gloves, but which Mom has time to put some on?