Considering all the positive outcomes arising from our public schools in recent years, it is somewhat disheartening to see the issue of turnover rearing its ugly head in Prince George’s County once more. All our advances will be for naught if this community fails to entice educators to spend their careers right here.

How has it come to this, again?

A nearly completed career in public education leads me to a single, inescapable conclusion. Call this Haines’ law: Systems of labor requiring unsustainable effort can never be taken to scale.

Teachers quickly realize that the assigned goal of reaching every child requires the deployment of nearly every waking hour to the preparation, delivery and evaluation of instruction. The message of “teacher do more” no longer plays very well to those dedicated educators who already devote nearly their entire existence to improving the lives of children.

Yes, valiant efforts do occur. Those stories can be inspirational, even transformational, but they have yet to be proven sustainable over time in the public schools.

Periodically, anomalous improvements in academic performance are generated in challenged schools. Such results most often involve a charismatic leader who inspires educators to heroic efforts on behalf of children.

Much-ballyhooed success invariably leads to promotions and transfers of valuable personnel in the attempt to seed other sites in the hope of generating like results.

Most frequently, in just a handful of years, such success stories begin the inexorable slide back to the mean. Simply put, there are limits to human endurance and patience. Heroism arises occasionally in extraordinary circumstances. It cannot be sustained as a workload or lifestyle.

In this age of increased scrutiny and accountability for educators, there will be some who ridicule the idea that teachers are assigned an unreasonable number of tasks to perform on any given day. Educators, however, know that the design and delivery of effective instruction too often becomes an afterthought on the administrative flow chart.

If this community fails to support and empower our highly performing teachers, those instructional leaders certainly will be the ones to seek out employers who will. It will be our children who suffer from our failure to learn from past mistakes.

Kenneth B. Haines is the president of the Prince George’s County Educators’ Association.