Halp pls: Why is the green scout unable to land a hit on the red scout as it runs away?

​

https://reddit.com/link/nnhkm6/video/snhoht3ka0271/player

It seems that every time I run away from another scout, the enemy always manages to continuously land hits on my scout. And no, I don't use waypoints (which slow you down).

Yet I'll often chase the enemy scout all over the map, and somehow their scout will either outrun mine or it will remain at an unreachable distance, as shown here.

I suspect the answer is simple: lag (fucking Comcast constantly chokes my region). But I'm hoping there's some mechanic I'm not aware of. Is there a way to run with your scout so as to not get hit by a pursuing scout?