I have only one suggestion which helped me pick out the good ideas from the bad - to get external opinion. It's almost like humans have a self defense mechanism

I have only one suggestion which helped me pick out the good ideas from the bad - to get external opinion. It's almost like humans have a self defense mechanism by which they can't adequately find flaws in their own selves and ideas. Thus, your idea might be the biggest thing in your mind, while other people might feel otherwise. That's why I told everyone about my idea - presented it in startup events, showed people demos, put it up on public mailing lists and wikis. The idea got battered and beaten down and each time there were little changes. There's this huge hype about being a "stealth startup" and a fear that people in some web shop will steal your idea and clone it. tl;dr - the idea that you start with is the one that people can't completely tear apart and obliterate. Also, the idea is pretty much useless. If I had an idea that I'll make a touch screen phone with an app store, nobody would've taken me seriously. If I'd pulled an apple and built one, people would've. Three months into full-time development of a product, I can only say that execution is pretty much everything.