According to the Wall Street Journal, Samsung may have been hasty in issuing a recall of the Galaxy Note 7 phone before adequately investigating what was causing its batteries to explode. From the WSJ:
The U.S. Consumer Product Safety Commission, which oversees product recalls in Samsung's biggest smartphone market, is expected to investigate whether Samsung notified the agency soon enough of dangers posed by the device. Samsung's decision to launch its own recall, bypassing the CPSC's formal process for a time, may have prevented regulators from figuring out more about the root cause, some U.S. lawmakers suspect.
Usually, companies work in tandem with the CPSC when making the decision to issue a recall; in this case, it took almost two weeks for the CPSC and Samsung to agree to a joint recall following Samsung's initial recall announcement.