Say you have created a piece of software, and now you are ready to launch it into the market. You start advertising, promoting and using other ways to persuade people to buy your product… But do you realize just how many potential buyers will never become your paying clients if the only interface you have provided is English?
Yes, you are right, English is spoken by millions of people across the world. But there are also other millions who don't know the language. Are you really sure you don't want to reach them? Aren't they good enough to be allowed to pay you for your product?
The same applies to your website as well. How many visitors do you have now? And how many more you can have if you add a non-English version? Making information easily available to the target audience is what websites are all about. And let's face it: in today's world, target audiences tend to speak different languages, because normally you don't address your message to your neighborhood alone. Website localization is an affordable luxury, and you will definitely like the competitive advantage it will provide to you.