It might amaze some people but people lie to SWs constantly. Because they're scared, intoxicated, protecting themselves or someone else, don't trust, don't remember, on principle, head injury, personality disorder, MH issue or bloody mindedness.
Then there's the imperfect information from HVs, teachers, HCPs, all with their own agendas.
Then there's your gut. Which you listen to but cynically because everyone carries their own prejudices.
And then there's the absolute worst thing. Which is this. If you do nothing, someone could suffer or even die. If you do something, you just did the worst possible thing; broken a family up.
Now imagine you have four of these cases, plus tens of other, less life-or-death. And you haven't slept because of stress and your relationships are suffering and you can't take a holiday and you're getting sick and you have your own caring responsibilities.
And every single day is like this.