EVEN WHEN the brightest executive is hired to rescue a bankrupt business, few people expect an immediate leap to profitability. Indeed, if the "savior" simply manages to keep the firm afloat, his or her first year is considered a success. But there is one kind of administrative post where unrealistic expectations and "burnout" are increasingly common -- superintendent of any large public school system.

"Urban centers are getting to the point where the job {of superintendent} is impossible. With the political climate, the dwindling financial support and unrealistic expectations, you know when you go in that you are doomed to failure," said Ken Underwood, president of a job search firm that specializes in school administrators.

The average tenure of school superintendents was once about five years. Now, it's only half as long, according to the Council of Great City Schools. In the Baltimore-Washington region alone, two superintendents have been fired, another is actively looking for a new job, a fourth is retiring and a fifth may be on his way out.

Too often, an immediate rescue is expected. But experts say the best superintendents need six months to learn the terrain and at least two years to achieve major academic improvements.

The number of academic success stories has dwindled, and that cannot be blamed solely on particular administrators or on political or fiscal climates. The demotions, dismissals and early retirements are too common. It is the job of superintendent itself -- and its relationship to school boards and elected governments -- that needs to be redefined.

In any enterprise involving thousands of employees and nine-figure budgets, effective management skills are crucial. It's possible that managers, and not educators, might make a welcome choice for some superintendencies, with deputies appointed to specialize in academic reforms.

It would be far better if superintendents delegated more responsibilities to competent deputies. Such an administrative group and a school board could then build momentum and confidence by agreeing at first on just one or two achievable goals where success is easily measured. This should not be a vague promise to "improve student achievement," but a clearly defined standard, such as bringing elementary school students up to grade level in math.

The groundwork for steady academic progress among students is laid with patience and reasonable expectations and not with the rapid turnover in superintendents that can be found in school districts around the nation.