Well ... for world domination I guess.Support in web browsers could make a huge difference.
Did you hear about FLIF image codec? Its author is working on the JPEG XL now, and all the best ideas from FLIF were used in the new codec, with some cool additions which make the new image codec truly universal. The format itself is basically a mixture of FUIF (from the author of FLIF), PIK and Brunsli image codecs. Google is already testing it in Chromium. When it is supported by major browsers, the format will become much more popular.
A similar thing could happen with a new cool lossless audio codec.