Read a numeric domain aloud to someone in Mandarin, Arabic, Spanish or English and it lands identically every time. That property is why numerics have held a durable international following while the keyword market went through its cycles. 4001 has a shape as well as a value. It’s the number just past a round four thousand, which reads as a model number, a room, a specification, a channel or a standard.

Four digits is phone-number territory, a chunk size people are already practised at holding in memory. That’s a genuine usability advantage and it applies in every language. Numeric domains are their own market with their own logic, and universality drives it. A four-digit string reads identically to a speaker of Mandarin, Arabic, Spanish or English, with no pronunciation problem, no accidental meaning and no spelling question. That’s why the short numeric sets held value through cycles that flattened the keyword market.