Ask HN: If a previous startup failed with your same idea, is that a bad sign?

Also, what percent of a startups (let's say app company) success is reliant on marketing?

This really depends on the vertical. Generally speaking, the less reliant on paid marketing you are, the better. Truly excellent apps market themselves. If you're entering into a niche vertical however, having to deal with marketing will probably be an unavoidable fact of life.

As far as competitors, it's almost always a bad idea to fret over the competition even if they're established. In this case they clearly aren't, so your only worry is whether to take heed of the fact that all of your potential competitors are basically dead on arrival.

As the other comments say, this really boils down to your judgement. Check out the other apps yourself, see how similar they are to your own execution ideas. If they're identical, you may have a problem.

There are many, many reasons that a startup may have failed (or is failing) and there still may be a product-market fit.

Some products & markets require you to go out and get users more than others, and they may not have done that.

It's on a case by case basis, just be sure to get validation for your project. Make sure that you're making something people actually want, and if they want it, how much they will pay for it. Can't stress it enough how important it is to go out and talk to potential customers, ideally hundreds, and figure out if they'll pay and tell their friends about it.

Marketing is important -- having a good landing/marketing page, getting press, etc. But at the end of the day the product is what will create retention. Looks get the first date, but your personality is what will get you the 8th date.

We can't really answer this question for you. You might spend some time reading startup post mortems. They typically include some analysis. Then, in cases where they get real discussion here, read the discussion. Don't assume that the people who failed know all the reasons they failed.

Edison made thousands of light bulbs that didn't work before finally making one that did work. There are a great many ways to fail. Their failure does not necessarily indicate anything about the odds of your product. It depends on a great many factors. Given that you have not linked to your thing or theirs and haven't even told us generally what you are making, this question is just way too vague. And perhaps that is part of your problem generally.

Does your app do something useful or is it a game? If it does something useful, do you or your company find it useful? Do you use it? Have you found earlyvangelists? Why do they like your product better than the competition? I put together this free risk calculator http://stts.us/StartupRiskCalculator that asks you to rate 9 strategic risk factors. The accompanying article explains each in more detail. The above questions focus on the first and most important factor, but the other 8 may be of use as well.

Is this a sign that no one wants this type of app or is this a sign that they failed due to not enough people knowing it exists (bad marketing)?

You tell us. This is your niche, you should get to know it better than any of us do. Use the apps, see if they have issues. See if there is interest for a better app than what currently exists.