Basically, if I take a step back from it, I think she had a bit of an attitude problem, because she was very mixed up about whether we were actually her parents rather than the kids' parents. So she asked us to drive her around in the evenings, snapped at us when we told her we weren't going to, expected us to be constantly on hand to look after the kids if she didn't feel like turning up, and expected us to teach her loads of things that she had already covered in training but was not interested enough to revise or look up for herself (eg what constitutes second stage baby food, how to dress children for different sorts of weather, and so on).
The consquences of all this were not great. We had a couple of incidences where she went AWOL and wasn't there to look after the children when she should have been, there were one or two minor but worrying issues with the baby (for example he got little welts on his neck from her ripping the bib off in a hurry, and when I told her not to do that, she tried to blame the marks on his dribbling, even though they were towards the back of his neck and obviously line shaped), I had to nag her to wrap the baby up warm in the cold weather after she brought him home crying with cold and his little arms like icicles, etc etc etc.
We have had the following in response to quite reasonable observations and requests about the children:
Us: Could you make sure you lock up the house and put the burglar alarm if you are last adult out of the house?
Her: That's proxy parenting!
Us: Why did you ignore our instructions from this morning about laying the table for dinner with everything the kids need, so they aren't making excuses about needing things and then running around the kitchen like maniacs?
Her: When do you expect me to reach these standards of perfection you demand?
Blondes knew about some of this as was recommending we get rid of her - well, she was right.
Agency are giving a 1/3 refund which is not unreasonable - they have been very supportive and done bags of work, including visiting her here for a day and makign sure she knew what she was supposed to be doing,