But seriously, from what I've seen, iteration is the best way to give birth to something real and useful into the world. There are just so many scenarios and edge cases that you will never think of until:
1) You're actually coding it 2) A real user is actually using it and fails
If two people of equal skills have the same idea and one starts coding and the other sits back to ponder the idea some more, my take is that the do-er will 9 out of 10 times beat the thinker.
I always have a thousand ideas in my head, and thinks about them in the shower, before I go to bed, etc. The good ones will tend to stay in my head and materialise more and more into a workable product and the bad (or just impossible) ones tend to fade away because I don't think about them anymore. The stuff I'm working on now has been an idea in my head for around a year, and I've thought about it every day. The result of this is that when I started coding I knew exactly what to make, and I haven't reimplemented or rethought anything because I know exactly what I want to make, down into almost every detail.
I came back to it about a month later and re-evaluated many things, and thought of newer, more clever ways to do certain things
Then I came back to it again about 2 weeks later and finally wrote out my "concrete" plan for Goal #1 and what I want done before moving onto the next phase.
As of writing, Phase #1 is almost in completion. Basically, just like your story, letting the idea sit for awhile gives you time to think it over, see how you can do things different, and get feedback so I think it's pretty valuable in some cases
It's a food item(s). If anyone's that curious, write me and I'll tell you about it. I guess for me 'lot of capital' is pretty much anything outside the software industry, not 'lot of capital' in more objective terms. I have no idea if it'd be realistic for me to attempt to do something with it, but I know people would like it, with a certainty that I've never had with any other product, which is why it amazes me that no one else has done this particular thing, as there are plenty of established players in the space.
Just like you use feedback from blogs to separate the good ideas from the bad, I usually show a few friends my prototype. I have abandoned several projects at the prototype stage, but that's more a question of "Is this something I want to commit a lot of time to?" rather than "Is this a decent idea?".
Whenever I have an idea, I want to act upon it immediately. And then continue to work on it. Sure, I will need occasional breaks, but this is what I think happens...
I find it a little easier to think about an idea when I have something sketched out on paper. I find it a lot easier when I have a prototype, no matter how limited. Both the processes of getting it on paper and getting it on-line clarify my thinking much more than just thinking about it.
I often have to crumple up a lot of paper and scrap a lot of code, but the paper and the code are not what's important. It's what I thought about while I did them that has advanced my thinking about the idea.
I think "good ideas", whatever that term means, motivates people to get into the arena. You need something that you feel makes sese with the world. Once you're in the arena, however, it's the flexibility and adaptation that matters. (Fair warning: I'm blowing smoke here, as all I've done is struggle these last few years)
There are two things that I have noticed. First, no matter what your idea or concept, once you put enough work into it you tend to get motivated. So motivation can come later, not at the beginning or a project. Second, really good concepts exist whether you work on them or not. I know -- I've had a couple of really good concepts I've worked on which didn't work out. My execution ability lacked. But the concept didn't just dissapear -- heck no. Some other groups with a lot more execution ability took them and ran with them. (and made a lot of money)
This leads me to believe that really good concepts are like races. Once you "get it", be assured that a dozen or more other people have it also. So you're in a race. I say take all the time you want finding something you feel has magic, but once you got it, run like heck as fast as you can, because time is running out.
I'm in a mode currently where I'm consulting and saving for a few months to run as a startup for a year or so. In the last couple of days I had one of those "ah-ha" moments that occur to me every few years or so. Quite frankly, it scares the crap out of me -- I'm not ready, it's bad timing, I don't have a team in place, etc. But once the idea clicks, the clock starts ticking.
BTW -- anybody interesteed in doing some P2P-type startup work and looking for a team, drop me a line.
EDIT: And I'm not actually an "idea" person. By good idea in this post, I mean a general fuzzy concept that maximizes dozens of criteria simultaneously: marketing, money, deployment, etc. It's an area of interest, perhaps a slogan. But not a concrete thing. You get the concrete thing by executing the concept in the real world, not by imagining it.
But other times, they rot, or become an unhealthy source of false comfort with inaction. This show from ZeFrank -- when he answers questions a bit of the way in -- really nails the danger:
http://www.zefrank.com/theshow/archives/2006/07/071106.html
For example, he observes sarcastically:
"If you don't wanna run out of ideas the best thing to do is not to execute them. You can tell yourself that you don't have the time or resources to do 'em right…No matter how bad things get, at least you have those good ideas that you'll get to later"