If you write software and people clone it, it's because you're not supporting the community correctly. Maybe it's because nobody can hack on your source code, or maybe your code sucks and nobody wants to work on it. Maybe you don't accept ideas and patches quickly enough. Maybe people don't like talking to you. Maybe it's just randomness.
Basically, software people like writing software, but often don't have a project that really excites them. Reading about something on HN gives them the inspiration to take that idea and implement it themselves.
So yes, if you're making a weekend project that is nothing special and don't want anyone to use, don't talk about it here because someone else will reimplement it. But if you look at complicated things that make money, like Flickr or YouTube, you don't see a lot of people cloning those because it's not as easy.
> it's because you're not supporting the community correctly
> Maybe it's just randomness
The latter part of your comment is completely correct, "software people like writing software" and that's often why they clone good ideas, the first part of your comment contradicts this. It has nothing to do with "supporting the community", people build their own versions of open source software all the time.
Sorry about that; I edited out a specific example.
search.cpan.org was the default interface to the CPAN for many years. The author didn't share the code and did't really take suggestions from the community, and so it got forked and is now gone. Nobody wanted to fork and rewrite the software -- it was good enough -- but the author wouldn't play ball with his users. Now everyone uses MetaCPAN.
Basically, software people like writing software, but often don't have a project that really excites them. Reading about something on HN gives them the inspiration to take that idea and implement it themselves.
So yes, if you're making a weekend project that is nothing special and don't want anyone to use, don't talk about it here because someone else will reimplement it. But if you look at complicated things that make money, like Flickr or YouTube, you don't see a lot of people cloning those because it's not as easy.