Hi Hugo, that has happened. But the hole idea is that you are the best person to take your idea to the highest potential. Idea X Implementation = profit.
If your implementation of a brilliant idea is bad, it doesn't matter.
So you just gotta be better than everyone else.

There's room for multiple implementations of the same idea - it's actually much rarer for a unique idea to be succesful than a non-unique one. So don't worry if someone copies you, it just means there's a market for your product.

Yes, working in public does increase the chance someone will take your idea or get inspired by it. But generally I'd say that the originality of your idea is, or at least, should not be what makes or breaks your product.

I don't share everything I do publicly, but I do share a lot. I find that there's a lot of benefits (getting product feedback early on, expanding by network amongst makers, getting more useful advice, etc) outweigh potential disadvantages.

Ideas are like your girlfriend's heart, if you don't give it care and she's always out there, then it's meant to be stolen.
People sharing their ideas are simply saying, "I'm the best bf so I don't think you can do better!"
Ideas you keep deep in your heart and so afraid of letting other people know, are just like the wives got their whole body covered by their husbands, nobody gives a shit, and also there are millions of them, exactly the same.

pick large, difficult markets. it won't matter... a rising tide lifts all boats. conversely, if there is no one doing the exact same thing, if may be too narrow... a feature not a product... or maybe the market is not there yet.

I've always found that telling people about what I'm working on led to progress, activity. whereas... working in isolation led to more isolation.

also, don't spend to much time looking for direct competitors or similar ideas. this has, in the past, caused me to spin my wheels and never get anything built. or in one case, continually redefining it so it was unique. I was building a product for a slidedeck, for investors, and not for the customer. kinda pointless -- regrets.

sive.rs/multiply