You're right, this will be a fast way to get people to stop telling you their ideas. But if you're trying to shut people up then you've missed the OP's point.

You can easily make normal people feel like their idea is worthless and you have mountains of business acumen that, obviously, they must lack. Do this enough times and what you'll find, just like you'd hoped, people stop telling you their ideas.

I'd argue that every time you do this you are shutting down opportunities to collaboratively create ideas that would probably work. Part of being "lucky" is increasing your exposure to failures [1].

When someone approaches you with an idea, you've certainly got a better feel for what will "work" more than you're average person. Consider taking the time to give feedback, help shape it, brainstorm with it. You might find that between the two of you what you create is bigger than what either one could come up with individually.

This applies in all areas of personal relationships, not just iPhone games.

[1] "To increase your chance of success, double your failure rate" - attributed to Tom Watson

My point isn't to "shut people up". If it was, that's what I would have written.

My point is to get people out of the mindset of "if I could someone ELSE to do all of the hard work, I'd be a gazillionaire."

My approach is to tell YOU how to seize the opportunity and get your idea rolling; I'm far too busy to do all of the work for you so you can retire rich, but I will gladly point you in a great direction and lay out your next steps. The reality is that you won't do it once you realize that YOU will actually have to do the grunt work.

To be fair, you wrote "the fastest way to get people to stop telling you their ideas" which sounds a lot like shutting people up.

To be fair, directly after the snippet you quoted, he had written "that they want you to build".

To be fair, again, if that was what I meant, that's what I would have written.

This could work :) I usually say, let's search the app store for your idea ... Just to see what comes up.

12 pages of the same idea later...

Moving on to other conversations.

Thats a great suggestion, I usually listens for some time and ask a few from my point of view meaningful questions. I usually finish off by asking them to send me an email and summarize their thoughts and to explain it in more detail.

Most of the times, the email never lands in my inbox, but when it finally does, theres usually something to it.

I've had that experience myself. Not only the same ideas pop up, but literally the exact same app name I had in mind.

I've found it just as effective to start giving them the resources to make their apps. Offer to lend them books and point them towards tutorials.

Nobody ever wants my books.

this is brilliant! in fact I used this technique out of instinct a couple of times (including with my father, who is an avid web app idea maker, lol!).