Instantaneous show of light why?

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When a light switch is flicked, the appearance of light is not truly instantaneous; it occurs too quickly for most to perceive. Electrical energy travels through wiring at approximately half the speed of light, resulting in minimal delay. The primary factor contributing to the perceived delay is the time required to heat the filament in traditional incandescent bulbs. In contrast, curly fluorescent bulbs may exhibit a more noticeable delay due to their design. Understanding these mechanics clarifies the phenomenon of light activation when a switch is turned on.
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Does anyone know a clear and absolute explanation of how is it that when you flick the light switch on there is an instantaneous show of light?
 
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It isn't instantaneous, just too fast for you to notice (unless using curly fluorescent bulbs).
The electrical energy travels through the wiring at about half the speed of light, so that doesn't take long. The biggest delay is the time needed to heat the filament in the bulb.
 

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