Well, it's possible she did not exhibit any overtly alarming behaviour over the course of the investigation. And yes, there are people who work in child services that suck at their job. There are instances of gross negligence on the part of the caseworkers. But it seems to me that it's a field that is usually woefully understaffed and so chances are increased for a person trying their best to do a less than perfect job.

I used to work for the government and spent months working an average of 10-15 hours a week in unpaid overtime in attempts to keep up with the insane caseload and lunatic clients, and was paid peanuts to boot. I don't know about other government employees, but I sure as hell wasn't being overpaid, and neither was anyone I worked with.