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For anyone who wonders why HR departments would ever adopt performance reviews with a "forced ranking," mandating that a certain ratio of workers get top and bottom scores, recent headlines have provided an answer.

On Friday, during a Congressional hearing into bonuses at the Department of Veterans Affairs, lawmakers quizzed a VA human resources official over eye-popping data that revealed all 470 senior executives at the VA received a grade of "fully satisfactory" or above in each of the last four fiscal years. In the most recent fiscal year, more than $2.7 million in bonuses were paid out to senior Veterans Affairs managers, and performance bonuses went to at least 65 percent of these top managers.

The bonuses have been the subject of much scrutiny for the role they potentially played in motivating VA officials to manipulate data to meet goals for patient wait times. And the VA's Gina Farrisee defended the agency's performance reviews in the hearing, saying the VA "has steadily made progress in evaluating and rating our senior executives using the five rating levels."

Yet the chart provided in Farrisee's opening testimony reveals that for four years straight, more than 70 percent of executives got one of the top two ratings and just 18 to 26 percent were deemed average. She also explained that the complete lack of executives in the bottom two ratings was typical for the federal workforce — just 15 top executives in the entire federal government received one of the bottom two grades in all of fiscal year 2012, she said.

But that is like saying it makes sense there were no Ds or Fs in one classroom because the rest of the school didn't have any below-average grades, either. If that's the case, chances are all the students (or all the federal managers) aren't actually that good, they're just not being graded objectively.

This isn't Lake Wobegon, as one lawmaker said in the hearing. It's a large and diverse workforce that is bound to have at least a couple of people — even among top managers — who simply don't pass muster. Top executives might very well represent the agency's best workers who have risen to the top. But a few of them, logic tells us, are still bound to have a bad year or fail to succeed in their new, bigger jobs.

This is why some HR departments launch "forced rankings," or "rank-and-yank" or Jack Welch's infamous "20-70-10" bell curve distribution. It's not because they're soulless automatons bent on making the rating of human performance an inhuman process. And it's not because they're mindless bureaucrats who adopt whatever consultants advise is the latest management fad. (Or at least, not most of the time.)

It's because they're frustrated that managers either don't have the guts to hand out failing grades or don't want to bother dealing with the fallout of telling employees they're below average. In other cases, there's no incentive for assessing people fairly. Unless they're forced to do it, many think: Why bother?

This is not to say the answer is to mandate that managers dole out a certain percentage of "5"s, "3"s and "1"s. That can add its own pile of problems. There are better ways to get people to offer candid assessments, such as training them to share bad news or rewarding them for fair appraisals.

It's also not to say employees need to be graded at all. More and more workforces are recognizing that traditional performance ratings are problematic and are doing away with them entirely.

But cases like the VA remind us why such dictates often get started in the first place. If a rating system is in place and nearly 80 percent of managers are deemed to be outstanding or "exceeding fully successful," something isn't right. If not a single top manager over four years gets a failing grade, someone's probably not being completely honest — and perhaps about far more than just employee grades.

Read also:

To change a culture, follow the money

The corporate kabuki of performance reviews

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