However, if Lojban only existed as some kind of experiment to test the Sapir-Whorf hypothesis, probably very few people would bother to learn it. In fact, Lojban's other uses have taken over so much that quite a few Lojbanists who don't believe much in Sapir-Whorf still use the language because of its other benefits. It lets you express ideas precisely, but allows you to be vague when you want to. It can easily express a much wider range of emotions than most natural languages. It helps you step out of your cultural conditioning.
Computers can understand it.
It's good for discussing philosophy. In the long-term, Lojban has more ambitious goals. As an interlanguage for translation - it would probably be easier and more accurate to translate from, say, Korean into Lojban then from Lojban to German, than directly from Korean to German. As a language for international law. As a way of improving our understanding of different cultures.