I've been a web developer for many years now but my main passion lies elsewhere (totally unrelated field), though I really enjoy my work and I'd like to think I'm pretty good it.

The thing is, I have an idea for a web app (yeah I know - bear with me!) and I think it could gain some serious traction if done properly. I have some pre-alpha stuff cobbled together and it's going well. Pretty soon I hope to bring someone else in and make a proper go of it.

But here's the thing - at some undefined future point I want out. In a full-time sense at least. As much as I enjoy this stuff, my other passion will require the majority of my time and given it's a huge money sink, I'm hoping this new hare-brained scheme will partly pay for it.

There's a lot said on here about having total ultra-focused passion to your project and how you'll fail to get anywhere/attract interest/attract co-founders with anything less. Is this generally true? I realise there are always exceptions but if it's true in general then it obviously makes things much more difficult. To be clear, I have every reason to want this to succeed and I'm willing to put the work in - it's just not something I want to be doing in 5 years time.

What would you say is my best way forward - keep quiet and see how things go and (hopefully) cash out in the future, or be totally upfront about my intentions at the risk of sounding somehwat flaky or uncommitted?