Can we stop with the uptime percentages?

Service reliability metrics like “four nines” uptime and glossy status pages are being criticized as opaque and often misleading, especially when they mask frequent, business-hours outages that halt real work. Commenters argue that uptime percentages don’t capture when and how failures occur, how they cascade through interconnected systems, or what they cost in lost productivity and revenue. Many call for more transparent, user-centric reporting—such as actual hours of disruption, frequency and timing of incidents, and standardized reliability indices—while noting the incentives providers have to underreport or spin outages.

Debate over uptime percentages and “nines”

  • Many note that “nines” are mainly marketing / contractual tools, not user-impact metrics.
  • Several argue that laypeople and execs don’t grasp how different 99%, 99.9%, and 99.99% really are.
  • Others say percentages are still useful as a simple proxy, especially for combining independent systems (multiplying probabilities).
  • Some industries (trading, emergency services, telecom, power) genuinely need 5–6 nines; for many SaaS cases, 2–3 nines may be economically sufficient.

Alternative ways to present reliability

  • Strong support for framing as time (e.g., hours of downtime per month) rather than just percentages; it feels more concrete (“1% is ~3.5 days”).
  • Counterpoint: “12 hours affected” is still ambiguous — one long outage vs many short ones is a very different experience.
  • Several want richer views: graphs over time, “average time between disruptions,” and user-centric measures like:
    • Business-hours uptime per region.
    • Weighted uptime based on actual request success.
    • Windowed user-uptime and electric-utility-style indices (SAIDI/SAIFI/CAIDI).

Timing and impact of downtime

  • Repeated emphasis that when outages occur matters more than total minutes.
  • Business-hours and peak-load outages are far more damaging than 3 a.m. maintenance.
  • Some note that in global services “bad hours” always hit someone, and outages tend to correlate with high load.
  • For certain workflows (e.g., long CI runs), even brief interruptions can waste hours of human time.

SLAs, contracts, and incentives

  • Discussion around aggressive SLAs (e.g., 6 nines) being realistic in some domains, absurd in others.
  • Sales often commits to high nines without engineering input; refunds are usually small and more about exit rights than real compensation.
  • Vendors sometimes exclude underlying cloud failures, weakening guarantees.

Status pages, trust, and transparency

  • Many feel official status pages under-report or downplay problems; third-party monitors are seen as more honest.
  • Some suspect large providers’ published uptime (e.g., recent GitHub/Microsoft issues) doesn’t match observed reliability.
  • Calls for status pages tied directly to external monitoring, auto-reporting all incidents, however small.

How much reliability is “enough”?

  • One view: most organizations overpay for marginal nines that don’t materially improve outcomes; better to invest elsewhere.
  • Opposing view: even short, rare outages trigger cascading operational, compliance, and reputational costs; enterprises value reliability above cleverness.