[Symbiote]

Without having a gap before you start, how do you plan on stopping in time if the car in front stops suddenly? Which they might do if they see someone running the red light, or a pedestrian thinking there's just enough time to run across.

[lsaferite]

The needed gap is proportional to your speed. Starting speed from a stop is quite low so the gap needed is low. As you gain speed you expand the gap.

[undersuit]

You can't all accelerate at the same rates and expect the distance between the cars to increase. The slow trundle off the starting line is needed to establish following distance.

[executesorder66]

That is why I said accelerate _slower_ than the person in front of you to build a gap. (Once you are on the other side of the traffic light)

When the light goes green everyone should go at the exact same time and acceleration. Because you just started moving your speed is very low, so you don't need a large following distance.

You are clearly one of the millions of people that doesn't understand this.