Why Accent Recognition Fails

Training Data Bias

STT models trained predominantly on:

  • Standard American English (General American accent)
  • Standard British English (Received Pronunciation)
  • Studio-quality recordings with perfect audio conditions
  • Native speakers with clear articulation

Result: Poor performance on non-standard accents, regional dialects, and real-world audio conditions.

Phonetic Variation Challenges

Same word, different pronunciations:

  • "Water" pronounced with hard 't' (British) vs soft 'd' sound (American)
  • "Schedule" with 'sh' sound (American) vs 'sk' sound (British)
  • Regional vowel shifts changing word recognition patterns
  • Consonant cluster reduction in some dialects

Missing Representation

Underrepresented accents in training data:

  • African American Vernacular English (AAVE)
  • Scottish, Irish, Welsh, and other UK regional accents
  • Indian English variations
  • Southeast Asian English accents
  • Southern American English dialects
  • Caribbean English varieties