Tracking a parcel

At first glance, this looked like a nonsense message -

There seems little point in tracking if the only information you get is that it's been signed for - after all, it's coming to you and you'd be the person signing for it, right?

Er, maybe not. In their haste to meet quotas for their rounds, it's entirely possible that the delivery ends up with a neighbour who, in the anonymous big city, you don't know. And that the "we left your parcel with your neighbour" slip goes missing. It's happened to us....