The power distribution system can be understood better when thinking about it as the vascular system of your vehicle. The fuses and circuit breakers, diodes and grounding points relate to the arteries, valves and veins of the vehicle system. Any malfunction of this system can cause strange and significant issues with all other systems of the vehicle.
You wouldn't ignore a potential circulation problem and you definately shouldn't allow neglect of your vehicle's power distribution system to cause an unexpected flat line in your car!