# Humans aren't fast enough for 4 9's

DevFeed: [Humans aren't fast enough for 4 9's](<https://devfeed.tech/articles/humans-aren-t-fast-enough-for-4-9-s-11819.md>)

Original publisher: [Read original article](<https://incident.io/blog/humans-arent-fast-enough-for-4-nines>)

Author: Norberto Lopes

Published: 2026-05-11T17:19:46Z

Content type: opinion

Language: en

Sources: [The incident.io Blog](<https://devfeed.tech/sources/the-incident-io-blog.md>)

Topics: [Availability](<https://devfeed.tech/topics/availability.md>), [Resilience](<https://devfeed.tech/topics/resilience.md>), [incident](<https://devfeed.tech/topics/incident.md>), [systems](<https://devfeed.tech/topics/systems.md>)

Tags: [autonomous](<https://devfeed.tech/tags/autonomous.md>), [availability](<https://devfeed.tech/tags/availability.md>), [dependency](<https://devfeed.tech/tags/dependency.md>), [incident](<https://devfeed.tech/tags/incident.md>), [incident-channel](<https://devfeed.tech/tags/incident-channel.md>), [incident-management](<https://devfeed.tech/tags/incident-management.md>), [incident-response](<https://devfeed.tech/tags/incident-response.md>), [on-call](<https://devfeed.tech/tags/on-call.md>), [outage](<https://devfeed.tech/tags/outage.md>), [post-mortem](<https://devfeed.tech/tags/post-mortem.md>), [recovery](<https://devfeed.tech/tags/recovery.md>), [resilience](<https://devfeed.tech/tags/resilience.md>), [slack-incident](<https://devfeed.tech/tags/slack-incident.md>), [systems](<https://devfeed.tech/tags/systems.md>)

## AI overview

The article argues that achieving 99.99% availability is fundamentally different from achieving 99.95%. Because the available recovery window is only 4 minutes and 23 seconds per month, human responders are generally too slow, so systems must provide autonomous recovery, redundancy, and enough resilience to survive critical failures before human intervention is needed.

## Source excerpt

Hitting 99.99% isn't a faster version of what you already do. It's a different problem to be solved: autonomous recovery, dependency ceilings, redundancies, and the discipline to build systems that buy you 15-30 minutes before you're needed at all.