Deutsche Bank's announcement that it will close its equities division, cut €6 billion ($10.1b) of costs and axe 18,000 jobs sounds extreme. But for Germany's biggest bank, which has muddled through the decade since the financial crisis with only incremental reforms and no credible vision for the future, the plan represents the kind of radical action that is needed.

A string of scandals and a persistent record of anaemic profitability have pushed down the share price to record lows. But while chief executive Christian Sewing should be applauded for a decisive plan, it would be premature to celebrate success.

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