One startup success, some profitable projects. Founded many which failed, invested in some failures, worked in several startups that failed.<p>1. Dishonest and manipulative cofounder. He pissed off every partner with aggressive negotiation, blatant lies, and bad deals. He was the type to agree to a deal, then back out and offer a worse one.<p>2. Founders were not committed. They invested a lot, sure, but didn't close deals. The key partner was rich but technically incompetent and didn't take the joint venture seriously. Project was simple but it dragged on for over a year, and neither party committed to get it done.<p>3. Good product. But founder oversold it. It didn't meet expectations, the blame was pushed to staff, eventually imploded.<p>4. Good product, good demand, but unit price economics didn't work.<p>5. Company was acquired for a profit. Acquiring company had no plans what to do with it. They cut off the primary target market immediately upon acquisition, lost a good chunk of sales. Nobody wanted to take responsibility for it and it died slowly after 3 years, and likely split the parent company as well.<p>6. Feature bloat. Hit crisis mode where everyone did everything and got nothing done. Pushing bad code to production, which broke. Had progress report meetings every 4 hours by the end of the project before everyone left.<p>7. Product was built. Sales co-founder lost nerve, despite a major airline showing interest, and abandoned it.<p>8. Company faked traction, e.g. buying products from the users and justifying it as marketing costs. Main investor lost nerve and pulled out. Founder could have saved it but was exhausted and pulled the plug.<p>9. Good product. Great team. Huge market. But one of the heads had very aggressively pushed the schedule, screwing over the entire product development plan. E.g. 6 months to release. Marketing wanted 2 months, QA wanted 2 months, leaving development with just 2 months. Dev ran on agile, QA ran on waterfall because they had to deal with visas and all. Crisis mode and meltdown.<p>10. Experienced, intelligent founders. Good business plan. But no budget and founder ran out of cash to keep it going. Would likely have gone well if founders had the money. Founder went on to do a startup about getting funding and it's still going.<p>tldr: A <i>lot</i> of this is just human problems. I think the point of failure for many startups is just stopping. Too many founders start a startup because it's to stroke their personal ego and once they have one, it gets neglected. Most people want some kind of passive income thing and won't commit to their startups.