Based on all the quarterly earnings results of JC Penney Co. Inc. (JCP) since bumbler Ron Johnson took over as chief executive officer, he should have been fired long ago. But there is one reason to keep him on the job: JC Penney cannot survive another "reinvention." 

A new CEO would believe that the retailer's approach to sales and marketing would need a complete overhaul. By the time that happened, JC Penney could be out of money.

Johnson may be the worst CEO that the retail industry has had in years -- perhaps decades. However, he may have learned a great deal from his mistakes. Whether he can turn what he has learned into a better plan to salvage JC Penney's fortunes remains a huge risk. But he has taken such a beating, and seen plan after plan fail, that he may be down to considering the few paths that might bring a very modest turnaround. JC Penney's best hope is pathetic, but it is all the retailer has left.

The evidence of Johnson's stumbles could not be more powerful. Revenue in the fourth quarter of last year fell by 28.4% to $3.88 million. Same-store sales collapsed by 31.7%. The results were even worse than in the previous three quarters of 2012.

Johnson has only once ace in the hole. JC Penney's largest shareholder and board member, Bill Ackman of Pershing Square, owns 18.7 % of the retailer. Ackman has allies on the board who hold even more shares. He essentially controls the public company. Ackman has said he will give Johnson three years to make JC Penney a success. Even if Ackman has changed his mind, his holdings are too large for him to abandon quickly. Ackman could recruit another CEO. By the time that person joined JC Penney and could set a new direction, 2013 would nearly be over.

The seeds of a long-shot success at JC Penney would come from Johnson's ability to finally admit that almost his entire plan to make the company a great retailer has failed. After posting poor results, Johnson said that the missteps where his. "I take personal responsibility for these," he said. Johnson also disclosed that he planned to return to some of JC Penney's traditions. As part of his rebuilding effort, he had rejected certain tricks JC Penney used for marketing that had been effective in the past. "We have brought back coupons for our rewards members. Although, we still call them gifts." He had killed the use of coupons last year.

Johnson is all JC Penney has left. If he has benefited from his colossal mistakes, the retailer has a very long shot of not failing entirely.

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