A friend's husband called one of the suicide lines and he wasn't committed or visited by the police, so it's not a 100% chance. I don't know the details of what the husband talked about, but it may have been because it wasn't a recurring problem. He'd just had an especially awful time at work for a few weeks, and eventually had a breakdown and called a hotline.

He quit his job a couple of days later and has been fine since, so maybe the person on the phone can make a judgement call on whether it's a recurring issue that needs professional help, or something that is an extreme response to an isolated incident and the person will be fine after they're "talked down from the ledge".