Who has never heard an employee ask this question?

“We’ve done it this way forever; so, why do we have to change now?”

While longevity is a decisive element in establishing a past practice, past behavior is not a Past Practice. Past behavior evolves into a Past Practice (in labor law) when it satisfies four conditions:

1. Clarity – (i.e., clearness, coherence, uniformity)
2. Consistency – (i.e., repetitious, regularity, reliability)
3. Mutuality – (i.e., shared knowledge and acceptance between parties)
4. Longevity – (i.e., a long enough period that employees, in general,
   rely on them)