Actually, I really mean 'looking after small children', whoever is doing it.
I used to hear this attitude from some men a lot at work - now I realise I'm hearing it from women too.
A few friends who work full time talk in very dismissive terms about what their nursery and childminders do - just changing nappies, wiping noses, singing a few songs, big deal etc. I think this is tied into a resentment about how much they have to pay for childcare, and I have a LOT of sympathy with that (have part time childcare myself), but I also think it has a lot to do with them simply not valuing the job of looking after their children.
More controversially, I have heard it from some working mothers about sahms. A kind of 'it's hardly rocket science, is it' attitude.
(Before I'm accused of having a wohp/sahm agenda - I am self employed (nothing to do with childcare!), main breadwinner, have one dc and share parenting with dp, along with some part time nannying, prob about 10 hours a week.)
I come from a background where family members have been involved in social work and child development, so I suppose I have always had some awareness of the developmental needs of small children and what happens when that care goes wrong.
So things like emotional development, building relationships, language and communication, social behaviour and self expression, along with the definable pre-literacy/numeracy skills are all part of the care of small children (and the big ones). And I think that's a HUGELY important job, whoever is doing it. I hear it dismissed as 'just playing' - which is when I think parents get angry about paying for it.
If we don't value that, why not? Is it because raising children has traditionally been seen as 'women's work' and therefore not important? Do other women buy into that attitude? Or does it date back to ideas about small children not being 'proper' people? (Victorians were big on this....)