test light correct use

    Question regarding video "Basic Electrical Review Part 1" under Basic Electrical Concepts folder. Time stamp 38mins - 39mins Paul covers using test light to energize control circuit of relay. I did the same test externally (as show in attached image) to practice using an incandescent test light to activate coil in a relay. But my test light bulb lit very dimly and coil field did work as relay did click. Why is that when Paul uses test light to energize coil in video, the light bulb in test light doesn't light up? isn't there current flowing thro the test light at that point in time when he is activating the relay coil?

The reason that the test light does not light is because of the resistance of the relay control coil. There is current flow, but the resistance of the control coil limits that current. There is enough current to activate the relay, but not enough to visibly illuminate the incandescent bulb.

This might not be a good analogy but, you can think of the relay control coil as being a "bad ground" that will not light a test-light.