If there were some kind of problem with the head where a ball somehow got dumped into the cabinet, this tray would catch it and dump the ball out at the scoop kickout. I've never seen that happen though. I can see how it may also safely keep wires away from the turning head.

In my opinion, this part isn't absolutely necessary, but it's nice to have for a complete game. The one I sold in October had one. The one I just bought last month does not

It's been 8 months since this was talked about, but I could use one too.