Resulting product is still geographically dependent, as with other approaches. Still need head count to manage separate product delivery for each target locale. Original engineering team may never see or care about resulting international product. Explosive growth in the Internet will accelerate users' expectation of language interoperability. One binary or set of binaries meets the requirements of all users, regardless of language or geographic location.
Single source is developed, compiled, and tested by one team, with no conditional compiles.
Testing is easier to unify into one team. Bugs are tracked and fixed once, including those resulting from UI language changes. Data interoperability between languages becomes obvious to the development and test team, as it already is to many users. Single source tree is easier to maintain, with no conditional compiles for international, no code propagation. Single worldwide binary fits well with movement to electronic product distribution, which fits into the world as a geographically independent model.