Why can labanotation record very precise timing in a dance?

Labanotation is able to record precise timing in dance primarily through the physical structure of its movement symbols. In this system, each movement is represented by a rectangular symbol, and the length of that rectangle corresponds directly to the duration of the movement: the shorter the symbol, the quicker the movement, while a longer symbol indicates a movement that is more extended in time.12

Because the system is an "alphabet" that spells out movement components, it allows for the clear statement of temporal relationships between individual movements. A particular strength of labanotation is its ability to show these precise gradations in timing, which can be recorded at a general outline level or with increasing specificity to capture every nuance of a performance.12