This read-only object reports the total count of bit errors accumulated during the BERT test's run time, and per the desc this value may not be available until the test finishes, with any value greater than zero causing the test to be marked failed. It's the primary quantitative pass/fail metric of the line-quality test. For example, an admin reviewing a completed BERT test with cXdslTestBertBitErrors reading a nonzero count would treat that as concrete evidence of a noisy or degraded DSL line, distinct from a sync-related abort.