Build: 46777 | OS: Windows 10 | Platform: Steam
Units don’t track down specific enemy targets in a dynamic, active way when using the default attack command (secondary click) over moving units).
- Select a melee unit. I recommend using a fast one, like the scout.
- Use the attack command (only once) over an enemy unit currently on the move.
That own units (and AI ones) track down moving targets dynamically, like when using attack move (although not attacking random enemies nearby, but specific ones). The idea is to not have units lose track of their enemies, like in the GIF below, where the first villager is identified as a target, and an opponent follows his path, tracks him down and intercepts him efficiently: