Johnson thought he was smarter than everyone else. His success at Apple reshaping the retail experience was a kind of a one-hit-wonder that he then thought would simply be a blueprint for any retail company.
He never had any success post-Apple like you say, but it wasn't because there wasn't any "insurance man". For me, I see it as a guy who found something worked smashingly, so he just assumed it would work everywhere else.
The stuff he pulled at JC Penny is a master class in what NOT to do in business:
After his success at Apple and Target, Johnson was hired as chief executive officer by JCPenney in November 2011, succeeding Mike Ullman, who had been CEO for the preceding seven years. Ullman then was chairman of the board of directors, but was relieved of his duties in January 2013. Bill Ackman, a JCPenney board member and head of hedge fund Pershing Square supported bringing in Johnson to shake up the store's stodgy image and attract new customers. Johnson was given $52.7 million when he joined JCPenney, and he made a $50 million personal investment in the company. After being hired, Johnson tapped Michael Kramer, an Apple Store veteran, as chief operating officer while firing many existing JCPenney executives.[11][12][13]
When Johnson announced his transformation vision in late January 2012, JCPenney's stock rose 24 percent to $43.[14] Johnson's actual execution, however, was described as "one of the most aggressively unsuccessful tenures in retail history". While his rebranding effort was ambitious, he was said to have "had no idea about allocating and conserving resources and core customers. He made promises neither his stores nor his cash flows would allow him to keep". Similar to what he had done at Apple, Johnson did not consider a staged roll-out, instead he "immediately rejected everything existing customers believed about the chain and stuffed it in their faces" with the first major TV ad campaign under his watch. Johnson defended his strategy, saying that "testing would have been impossible because the company needed quick results and that if he hadn’t taken a strong stance against discounting, he would not have been able to get new, stylish brands on board."[12][14]
Many of the initiatives that were successful at the Apple Stores, for instance the "thought that people would show up in stores because they were fun places to hang out, and that they would buy things listed at full-but-fair price" did not work for the JCPenney brand and ended up alienating its customers who were used to heavy discounting. By eliminating the thrill of pursuing markdowns, the "fair and square every day" pricing strategy disenfranchised JCPenney's traditional customer base.[15] Johnson himself was said "to have a disdain for JCPenney’s traditional customer base." When shoppers were not reacting positively to the disappearance of coupons and sales, Johnson did not blame the new policies. Instead, he offered the assessment that customers needed to be "educated" as to how the new pricing strategy worked. He also likened the coupons beloved by so many core shoppers as drugs that customers needed to be weaned off."[11][12][13] While head of JCPenney, Johnson continued to live in California and commuted to work in Plano, Texas by private jet several days a week.[16]
Throughout 2012, sales continued to sag dramatically. In the fourth quarter of the 2012 fiscal year, same-store sales dropped 32%, which led some to call it "the worst quarter in retail history."[17] On April 8, 2013, he was fired as the CEO of JCPenney and replaced by his predecessor, Mike Ullman.[18][19]