Why Business Needs SRE? Translating Reliability into Money

In the IT world, there is a myth: "A good sysadmin is one whose systems always work and never crash." In the reality of 2026, chasing 100% uptime can bankrupt a company faster than a server crash. Enter Site Reliability Engineering (SRE) — a discipline that turns reliability into an economic metric.

Google's Reliability Paradox

The SRE concept, born at Google, states: 100% reliability is not the right goal for most services. A smartphone user in the subway won't notice the difference between 99.99% and 99.999% availability, as their mobile connection drops more often. But the cost of that "extra nine" for the business grows exponentially.

Key Metrics: Speaking the Language of Money

SRE operates with three concepts that connect the technical department and the business:

• SLI (Service Level Indicator): What do we measure? (e.g., API response time < 100ms).
• SLO (Service Level Objective): What goal do we set? (99.9% of requests must be successful).
• SLA (Service Level Agreement): What happens if we fail? (usually fines in the client contract).

Error Budget

This is SRE's most revolutionary tool. If your SLO = 99.9% per month, then you have 0.1% downtime allowance (about 43 minutes). This is your "budget".

SRE Rule: As long as you have an error budget, you can take risks. Deploy raw features, run experiments, refactor the core. But once the budget is exhausted — all new releases are frozen ("Code Freeze").

How NineLab Implements SRE?

We don't just set up monitoring (Grafana/Prometheus). We change the culture:

1. Shared Responsibility: The developer whose code "dropped" prod participates in the incident review.
2. Blameless Post-Mortems: We don't look for the guilty. We look for the systemic reason why the test missed the bug.
3. Automation: SRE should spend no more than 50% of time on routine ("toil"). The rest is for writing code that eliminates routine.

Conclusion: SRE is an insurance policy for your innovation. It allows you to move fast where it's safe, and brake where risks are too high.