the.com/availability
The promise that you'll actually be there when someone needs you, machine or human.
means The degree to which a system, service, or person is ready and reachable when required.
from From Latin valere, to be strong or worth something, via avail; the quality of being able to be used arrived in English by the 1800s.
Nine nines99.999% uptime allows about five minutes downtime yearly.
Dating slangEmotional availability now matters more than calendar availability.
Engineering trioPairs with reliability and maintainability in systems design.