Inertia Switch question

[Outatime]

While I was looking at the footwell photo, I remember I always wanted to ask the use of the black box with the red "button" on top....



I recall it's the inertia switch... and it's suppose to control the fuel pump (just like an on/off switch)....

But I remember that the car could starts and run in both the "on" or "off" position.... is that some wiring fault!?