Two of a trade seldom agree.

People who do similar work may still hold sharply different opinions. Shared expertise does not guarantee that they will reach the same judgment.

The proverb presents disagreement among professional peers as a familiar tendency, not an inevitable result of working in the same field.

Use it to comment on a disagreement between people who practice the same trade or profession, such as a dispute over how a job should be done. It need not imply that either person is wrong.