Sony cited poor sales in its smartphone business, due to major competition in the space.
"The new MRP (Mid-Range Plan) was modified to address the significant change in the market and competitive environment of the mobile business," Sony said in a statement. "Under the new MRP, the overarching strategy for the (mobile) segment has been revised to reduce risk and volatility, and to deliver more stable profits. This revision includes changing the strategy of the (mobile) segment in certain geographical areas, concentrating on its premium lineup, and reducing the number of models in its mid-range line up."
Sony has taken significant share in Western Europe, as high as 11 percent by some accounts, but the price reductions and marketing have taken their toll on profits. Sony also has no share in the U.S., at just 0.2 percent of the market dominated by Samsung, Apple and LG.
Sony has always been a relatively premium brand in its tech offerings (or at least that's where they tend to place themselves with their pricing, hardware usually reflecting) so I don't think that they should be trying to make offerings in the low-end mobile market anyway.
The Z2 was quite an impressive phone, and both the Z3 and Z3 Compact are very good. If the Nexus 6 ever comes and its camera is typically lackluster, I may well buy a Z3 as my next phone.
Edit: And if the Z3 launches on all carriers in the US, which it might (?), then I think they can expect a considerable (relative) market share boost.