A new report by DigiTimes suggest that Apple has already narrowed down on Quanta Computer for mass producing their 2nd generation Apple Watch (2016) in Q2 2015. The report states that Apple had initially planned to split the mass production of their new smartwatch between Quanta Computer and Foxconn Electronics. However they changed their mind in the last moment.
A probable reason behind such a move is Apple's hunch for low sale volumes for their second generation watch. While Apple may be claiming 50% of the market share in the smartwatch department it is still nowhere near its sales volumes when compared with the iPhones or the MacBooks.
In fact the Cupertino giant has already reduced its shipping twice in a span of few months - once in 2015 and yet again in 2016. With gradual increase in popularity of IoT (Internet of Things) devices, the demand for smartwatches will increase, but till then it seems Quanta Computer is right mass producer to vouch for.