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incident low confidence: confirmed status: factual

McDonald's ended its IBM AI drive-thru pilot after repeated order errors

2024-mcdonalds-ibm-drivethru-ended · 2024-06-17

Across 100+ US locations, McDonald's IBM-built AI voice-ordering system repeatedly misinterpreted orders — documented examples included adding bacon to ice cream and hundreds of chicken nuggets — especially under noise and overlapping speech. McDonald's ended the pilot in mid-2024.

System

Framework
McDonald's / IBM AI voice-ordering (drive-thru)
Tools
voice-ordering
Vendor
McDonald's / IBM
Autonomy
supervised-autonomous

Classification

Primary class
task-failure
Chain
task-failure/misunderstanding
Attack vector
n-a
Causation
entity: ai · intentionality: unintentional · timing: post-deployment

Trigger

Across 100+ US drive-thru locations, the AI voice-ordering system repeatedly misinterpreted orders — documented examples included adding bacon to ice cream and adding hundreds of chicken nuggets — especially under background noise, accents, and overlapping speech.

Root cause

The system could not reliably understand real-world drive-thru speech conditions, and misorders required frequent human correction, undermining the automation's value.

Contributing factors

  • Speech recognition was not robust to noise, accents, and overlapping speech.
  • Human staff had to intervene frequently, negating efficiency gains.

Detection

Widely documented through customer videos on social media and subsequent reporting.

Recovery

McDonald's ended the IBM pilot in June 2024, with the technology switched off at testing locations by late July 2024; it signaled it would explore other voice-AI vendors.

Prevention

Validate speech systems under realistic noise/accent conditions before scale; set accuracy thresholds and human-fallback design; pilot with clear success metrics before broad rollout.

Blast radius

User harm
No safety harm; degraded customer experience and operational burden as staff had to intervene and correct orders, with reputational impact via viral videos. reputational
Scope
100+ drive-thru locations
Reversibility
reversible

References

Tags
voice-ordering operational pilot-ended

Sources

Cite this incident

@misc{2024-mcdonalds-ibm-drivethru-ended,
  title = {McDonald's ended its IBM AI drive-thru pilot after repeated order errors},
  year = {2024},
  howpublished = {agent-postmortems},
  url = {https://swarmproof.github.io/agent-postmortems/2024-mcdonalds-ibm-drivethru-ended/}
}