If you ever get curious, take a half dozen different manufactures plugs and measure the resistance between the cap and the center electrode. You´ll find some really large differences. And if you've ever have the opportunity to watch a plug fire on an oscilloscope and being able to freeze the picture, you´ll see why some work better than others.
The engineers give you an oscilloscope picture (usually produced with a specified voltage and resistance), that you try to match in the vehicle. Resembles a peak with a couple of bounces afterwords. I've seen the picture on the scope, look like static, which can´t be good. Some of it's plugs, some resistance in the wires and connections, some is how close the ignition module is to optimum. Some is even fuel, compression and valve timing.
There is a rather large difference between wrong, acceptable and optimum. Electronic ignitions, generally perform better anyway. But the engineers work really hard to get a predictable igniition and burn, plug splash messes up the works. More spark isn't necessarily better spark. Some octane knock, can be traced to plugs.
I´ve found in a system that's matched well, the plugs tend to last forever.