Implicit in the claim that something is a “best practice” is the assumption that another department’s circumstances are the same and problem is the same. Then the transplanted practice will take root and flourish. What may be a best practice under one circumstance may not hold true if those background facts change. Likewise, if the problem differs, the practice may no longer be best.
If you call something a best practice, you are declaring that, all other material things being equal, other practices are inferior. On the other hand, if you decry some practice, you are not nominating any other practice as the preferable alternative. Thus discussions of best practices have inherent asymmetry.
Besides the assumption of contextual stability and critical asymmetry, there is longevity: the duration of a best practice. Is it not inevitable that a best practice eventually slips behind a better practice? How can a best practice stay on top forever? Three servings for thought on best practices (See my post of June 6, 2006: best practices and references cited.).