Earlier quoted context omitted.
I think Matt Levine's take on this is right on: https://www.bloomberg.com/view/articles/2016-09-09/wells-far... . Senior management wanted employees to do REAL cross-selling to make money, but the metrics were set so high that employees turned to fake accounts to meet the standard. The fake accounts did not benefit the bank in any substantial way: So that's about 2.1 million fake deposit and credit-card accounts, of…
It doesn't seem possible that 5000(!) employees did this and the CEO had not a clue.
He can only create structures (e.g. internal audit team) that are powerful enough to detect it and report it to him.