I've been through 2 failed startups, a handful of failed ideas, and also serviced a variety of clients with "startup" ideas that failed. Suffice it to say, I'm quite experienced with failed ideas. Therefore I wanted to share some criteria that I'm using on my own idea selection this time around.

Note: This is for new groups, developers, entrepreneurs that don't have some monolithic base of capital/funding to support them.

It Should Be For You

This. This needs to be the first and foremost. Ask yourself honestly -

Will I Use It?

And be brutally honest with yourself. Don't kid around and say, well yeah I could see myself using it. Because not being honest with yourself will only decimate things in the short and long run.

What I've Learned from Experience on This

New ideas, products, startups, software, etc. are already a large gamble (whether you want to admit it or not). When either I or clients would attempt to execute an idea for a group we/they are not a part of, a handful of things would go wrong:

Focus is often on the wrong features. After all, if you're not the one using it or have the need for it, it's a hit/miss with what the prime focus should be.

It's built for the wrong group. My teams were guilty of building it for startup accelerators or VC. Most B2B clients are guilty of building it for the "buyers" instead of the users. Most, in general, are guilty of building it for this mysterious "they" group. "They'll love it." "They'll buy it." "They'll definitely use this."

It's marketed on the wrong channels. If it's for you, then identifying the best way to get the message to your audience is FAR easier. In fact, you're probably already a part of a network you can distribute this in. If you're not... well then you will probably: (a) Make a landing page; (b) Make a Facebook and Twitter Account; (c) Spam everyone you know the day you're done; (d) Spam tons of people you don't know; (e) Bug a variety of news source authors you've never talked to to write something about you; (f) Setup a faux blog that will only post material that's clearly for marketing.

The message is completely wrong. Related to the previous point, but this is when people start using wording like "revolutionary" or "leadership" or "quality" or "for everyone" type wording. The problem gets lost in the maker/team's confusion of what the main message should be to users.

It doesn't get tested realistically. This. This. This. It usually barely gets tested at all, but when it does, it doesn't get tested like an actual USER would use it.

Not picking something for yourself is... well ... very egocentric. It's saying "I understand your problems even if you don't!!" And sure, if you have enough resources (or luck) you can test away until it does. However, by the time you're down tooling it, it will likely be completely different from where you started.

The worst is when the team or group starts talking in an almost condescending manner about their users. "They definitely need it because they're terrible x and this will help them." or "They definitely need it because they have no grasp on x or y."

The biggest benefit of this one is that... well if no one else uses it, at least you will!

It Should Provide Internal Motivation

Just because an idea is valid does not imply that it will get done. Just having enough money doesn't imply that it will get done. Just having enough time doesn't imply it will get done. For independent ventures that require one to manage a job/family/etc and execute the idea on the side... WANTING to do it is necessary.

For example, I would definitely use a web service that wrapped all government form related websites into an easy to use user interface that explained the nuances in plain english. However, I have absolutely no desire to develop a web scraper for doing so, learning the different terminology to translate into plain english, or going through any regulations to make sure that the service is legal. Therefore, after I've worked a full day and have some time to do my own thing, it's very unlikely I'll touch this idea.

So, yes, you can find ideas that no one else wants to solve and call them unique. But mustering the gung-ho to execute them after a long day will be very difficult.

It Should Be Within Reach of Your Abilities

My second startup sought to create a triple A game title that tested your personality. It would deliver a highly accurate result due to the following scenario:

What will gauge your personality better:

If I ask you on a written test how you respond in group conflicts. If I immerse you in a post apocalyptic game where yourself and a group are making a decision on where to hide from a band of blood-thirsty monsters.

Myself and my partner, who was a Ph.D in this area, knew that we would totally use this. We also we're highly motivated to do so. Unfotunately, the resources it takes to produce such a high quality environment were unrealistic. I know 3d programming and game concepts, but creating unique models (characters) and environments was far beyond our reach.

Yes yes, there's always the whole "well you can just take it slow and etch a bit off little by little." Unfortunately, gargantuan projects can feel like an endless marathon when you wind up spending most of your time learning or recruiting instead of making real progress. And again.. for those of us whom lack prolific resources... chasing something like this after a full work day is insanely difficult.

If it's within your abilities, you'll experience momentum. And momentum is indispensable.

Tl;dr: Be your own market. Make sure you have a desire to build it. Pick something that you can accomplish within a reasonable time frame.

This is obviously just from my experience and observations. I'm not asserting that this is absolute truth by any means.