The speed at which this news comes out surprises me a little. In my experience, most Boards of Directors are willing to give a management team with a pretty good track record a chance to turn things around first before they go nuclear. Although, that chance comes with the provision that they feel the management team has a good strategy going forward. Rule number one when you stand in judgement before a board with lackluster results, you always followup with the plan. You want to be prepared to pivot the conversation to questions of the future and away from what happened in the past.
It could be that Samsung’s management team didn’t show that they were planning on anything other than more of the same. This left the board with the uneasy feeling that they better step in sooner than later. Or when everyone started scrutinizing Samsung Mobile’s detailed income statements by product line everyone started asking why these guys are throwing money down ratholes with no real oversight? Now as punishment, someone will be moved into control of Samsung Mobile with the mandate of "cleaning house".