It has been a long time since Zimbabwe has been on the front page of UK papers, even the free ones and often the lead item on TV news. So looking around I found these articles that help to explain what happened and why.

An academic background paper on the Zimbabwe military and their commercial activity - copied from China: 'The Curse of Military Commercialism in State Enterprises and Parastatals in Zimbabwe'.
Link:http://www.tandfonline.com/doi/full/...0.2016.1145981

By an American academic @ Edinburgh University: 'Mugabe's fall from grace unlikely to end Zimbabwe's political infighting and economic decay' and sub-titled The outlook in the breadbasket of southern Africa looks far from rosy with a leadership new in name alone.
Link:https://www.thenational.ae/opinion/c...decay-1.676238

Self-explanatory and short via WaPo: 'To understand the coup in Zimbabwe, you need to know about Grace Mugabe' by a Zimbabwean in exile.
Link:https://www.washingtonpost.com/ampht...-grace-mugabe/

Another author in exile: 'Power to the party: Zimbabwe’s coup isn’t a revolution but a consolidation'. This ends with the best summary I read today:
What has happened in the past two weeks, and has come to fruition in the past 48 hours, is ultimately an internal adjustment. From the perspective of ZANU-PF, an immature and greedy challenger has now been silenced by the adults in the room. This is no revolution giving the power to the people. The army has done its duty in giving the power back to the Party.
Link:http://africanarguments.org/2017/11/...onsolidation/?