It's easier to hold one of the contacts of the battery directly on the bulb and one end of a single wire on the bottom of the battery, all with one hand, then use another hand to touch the wire to the other contact on the light bulb. The problem is they didn't intuitively understand bigger light bulbs when operated on lower voltage (and thus lower current).

The funny physics answer would be to assemble correctly and then point out that it's lit, just exceedingly dimly (producing mainly IR).