Sony to focus on high-end devices in favor of low- and mid-range ones in order to increase profitability

The most likely reason for this is the hard competition that comes straight from various named and unnamed China-based contenders, which undermine Sony's hard-earned position in the non-flagship segments as they offer more power- and feature-laden devices in the similar price range. This better “bang-for-the-buck” ratio is apparently hurting Sony's sales very much. The company is not among the top smartphone manufacturers, both regarding shipment volumes and overall cash brought home. It's getting harder to battle the fierce and ever-growing competition, and the market leaders – Apple and Samsung – seem to be unreachable at the top of the smartphone food chain.
Sony is already tipped to be making waterproof mid-range devices a standard in the next year (which will further up its game against the rivals' mid-rangers) and is also ceasing to develop firmware updates for some of its older mid-rangers (the Xperia SP, for example) – this might be the clearest evidence towards an internal change of heart.
source: DiGiTimes
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