These days in StarCraft we have a good amount of commentators I’d call decent, some that personally I find pretty bad, and a couple that I’d say are great. I think a lot of commentators miss some of the basics that make all the difference.
The cornerstone of good StarCraft commentary (outside of everything that goes along with being on camera and public speaking, which is obviously huge) is being able to quickly identify the build order, and/or unit composition being used by each player and being able to explain how these interact with one another.
A very simple example that can demonstrate this is a Zerg player using 3 base speed roach baneling timing on WhirlWind in ZvT against a Terran playing going for a greedy 3 command center before factory build. The sooner a commentator can identify what builds both players are going for and recognize how the build orders will interact (the zerg player needs to outright win or kill 30-40 scvs as well as infastructure), the sooner they can begin explaining that and build up hype to that engagement, which will inevitably decide the game.
Very often I watch games, and a crappy commentator is only able to realize this attack is coming when they see roaches and zerglings moving across the map, marginally better commentators will see it when the roaches are in the production tab, better commentators will start to see it when they see a zerg player syncing up roach and baneling speed upgrades and making 3-4 overlords at once so they can use up that big spike of larva, the best commentators will be MUCH earlier taking note of a lack of evolution chambers, the zerg cutting drones at around 45, not bothering with much creep spread, and much more.
While every technical detail leading up to an all-in or timing attack does not need to be thoroughly explained by commentators, as it can become overly technical and boring, as well as sometimes repititive, the more aware of these details the commentator is, the better they will do.
The sooner a commentator can start hyping up the upcoming key engagement that will decide which player will get far ahead or potentially win the game, the more enjoyable the game is to watch and listen to. There’s nothing worse than having a commentator completely misread an attack and not understand when an attack is simply harassment/pressure, and when it is a committed attack that must do crippling damage or outright win, its as if a writer is writing a book and the climax of the story is skipped over as a minor detail in the plot, and the focus of the writing is entirely elsewhere.
It might sound obvious, “identify the build orders of each player” but explaining how the builds will interact and the implications of their choices on how the game will play out is the important part often missed. Tastosis manage to get away with often spending the least amount of the time talking specifically about the game being watched, but because Artosis is able to almost always quickly and concisely explain the interactions of the building orders being done and the timings of these builds, they get away with it easily.
StarCraft is a game with a lot of downtime, compared to other sports/esports where a lot is constantly happening, and to keep the audience engaged and interested during that down time, in my opinion this is the most important thing to do this is why building hype, excitement, tension and interest towards that key engagement(s), is of the utmost importance.