That's how people commonly give time in my language, I suspect mainly out of convenience:
Quarter hour precision is possible to achieve with at most five syllables (and typically just two); compare that to minute-level precision, which usually takes at least 5 and sometimes as many as 10.
Interestingly, spoken times also commonly use the 12 hour clock, while times are almost exclusively written as 23 hours.
Quarter hour precision is possible to achieve with at most five syllables (and typically just two); compare that to minute-level precision, which usually takes at least 5 and sometimes as many as 10.
Interestingly, spoken times also commonly use the 12 hour clock, while times are almost exclusively written as 23 hours.