Samsung was forced to recall its Note 7 handsets when some started catching fire. Initial replacements also proved combustible, so eventually there was a global recall and Samsung disabled all non-returned devices (Samsung Bricks Remaining Note 7s). There were many theories as to why the handsets caught fire, some blaming the overly thin design and others the battery, but the mystery is to be solved on January 23rd, when Samsung will reveal the results of its investigation at a press conference.
As a result of extra engineering to ensure no repetition of this problem, there are rumours that the launch of the S8 will be deferred from the MWC event to around the middle of April.