There is niche technique in Tetris called Z-spin. Here is what it looks like.
Correct Z-spin
Here is another Z-spin, but note the position of the pivot point.
Incorrect Z-spin
Why did the second Z-spin not slot in? This seems so arbitrary when the first pieces rotated ⟲⟲ where as the second piece rotated ⟳⟲.
The answer lies within the details of how modern Tetris Super Rotation System works. The pivot point on the Z piece is asymmetric.
Attribution https://harddrop.com/wiki/File:SRS-pieces.png
At some point in the past the pivot point was implemented this way, then later was codified into the modern Tetris Guidelines as SRS.
Had Z-spin been deliberately designed, a real choice could have been made. The options would have been:
Given those 3 options, it would be silly to pick the current system as option 1 is superior if Z-spins were desired at all.
The Tetris community as a whole is harmed by this accidental complexity. New players need to learn arbitrary mechanisms instead of honing the key Tetris skill, stacking blocks. The current system artificially created an uninteresting “skill”.
We do want games with depth and a high skill ceiling, but also to avoid arbitrary mechanisms that only hurt new players. New players are the lifeblood of communities. Let’s design welcoming games instead of ones with papercuts.
Do you want to avoid accidental complexity and design deliberately? You’re in luck, Battlefy is hiring.