I term the first few months of your FDW settling into your home as the "teething" phase. This is also the likeliest period that employers could inevitably end up frustrated when expectations are not met, fast. This is especially so when the household involves our children and loved ones.
What I suggest would be to maintain firmness with regards to your requirements but to always allow for open communication. This could include going through with her certain errors, if committed and also the reasoning behind it whilst maintaining mutual respect.
A positive reaction could generate a positive response, lift their spirits and serve as encouragement for taking care of your household and children well. Should mutual respect be bridged however, this could not only discourage your FDW but affect her physical and psychological state of mind and in turn her ability to perform.
She could even be afraid to ask questions or clarify on her tasks and commit further errors on the job. "For how long should I be patient with her?", asked an employer to me. To put simply, every individual has a different learning curve. The employer himself would have the best gauge on his foreign domestic worker's attitude. it is both parties responsibility to jointly building up that trust.