The importance of internationalization and localization
Imagine that you just bought an imported sound system. You open the box, find an instruction booklet written in your language, and begin reading, but you soon notice:
The language of the booklet sounds stilted.
The punctuation and capitalization do not use the rules of your language.
In the section on basic setup, dates and times are not formatted the way you are used to.
Some of the illustrations contain text that is not translated into a language you understand.
You you may worry that the sound system might not perform satisfactorily for you and that it might not be of good quality. You might decide to exchange it for a competing model.
The same scenario can occur with software. Consider a product that you market internationally and that you have not fully localized. Your international customers, noticing that the product was not designed with them in mind, might conclude that the product will not perform satisfactorily for them, and might exchange it for a product from one of your competitors.
To avoid this, make sure that any application you market internationally is adapted appropriately for each region's users.
The language of the booklet sounds stilted.