«You don’t need to overtake in traffic, you’ll be stopped at the next red light anyway.»
Nothing could be more false!
Traffic is not linear but is a step function that has as its upper limit the speed at which you can drive in the absence of traffic (and red lights) and lower limit the speed of the old lady glued to the steering wheel who goes to church on Sunday and only uses the car for that occasion.
So, if you overtake the idiot going 29.9 km/h on the speedometer (which let’s remember is not really 29.9 but something around 28.405km/h according to the manufacturer’s preference) and who stops at the traffic lights before the yellow light comes on, automatically, in addition to recovering 4.595km/h, you will have avoided waiting at the traffic lights those 2-5 minutes. So let’s say you’re potentially on time for an appointment considering the ideal case based on statistical traffic, if I’m in front of the old man with the hat driving a FIAT UNO, maybe I’d better overtake him even if at the first traffic light I find him behind me. This is precisely because the old man will stop at the first warnings of the setting of the green and consequently, if I don’t overtake him, I will lose three minutes at the first traffic light, 2.5 minutes at the second and so on (we are clearly going offroad here).
Every old overtaken unlocks the possibility of arriving on time.
Why talk about traffic when we could be in the countryside? Because traffic lights are a filter: whoever is at the right time in the right place goes ahead, the others wait patiently. If a company is at the wrong time in the wrong place it will probably fail in some way (arrive late to the hypothetical appointment in the previous example).
If a vehicle manufacturing company does not receive the screws in the necessary quantity and quality, it will not be able to finish building vans, which would be used to deliver other goods used in turn for other purposes…etc. If this happens sporadically, it is not a problem, you overtake the old man and move on, but if the road is full of old people so that the traffic is completely blocked or from one day to the next they take it from the 50 limit to 30 and the police car stands ready at the crossroads just waiting for you to overtake, then there is nothing you can do, maybe walking is the only option.