The unusual declaration by the Fed comes in response to "pervasive" consumer abuses and compliance breakdowns at the bank.
The firm did not have an effective firm-wide risk management framework in place that covered all key risks. This prevented the proper escalation of serious compliance breakdowns to the board of directors. The Board's action will restrict Wells Fargo's growth until its governance and risk management sufficiently improves but will not require the firm to cease current activities... Emphasizing the need for improved director oversight of the firm, the Board has sent letters to each current Wells Fargo board member confirming that the firm's board of directors, during the period of compliance breakdowns, did not meet supervisory expectations. Letters were also sent to former Chairman and Chief Executive Officer John Stumpf and past lead independent director Stephen Sanger stating that their performance in those roles, in particular, did not meet the Federal Reserve's expectations.
https://www.federalreserve.gov/newsevents/pressreleases/enforcement20180202a.htm