It is somewhat akin to spec work within the design field[1], in that only the top performers make money and everyone else goes home empty handed despite their hours of work. However, I've noticed that most of the near-winners tend to open source and share their solutions on GitHub, so one could argue that it helps the community (unlike say 99 designs, on which non winning entries are basically worthless).

[1]: http://www.nospec.com/faq