I have never been at a startup that failed for technical/technology reasons. All failures I've seen were due to issue with delivering what customers were interested in paying money for. Most often, product owners and developers were not able to establish good communication, which led to developers basically creating a product that didn't match what customers wanted. Period.
I would be interested in your definition of technical debt though. What some people call "technical debt" or "hack", I often call "the best/fastest way to address the current business concern and deliver immediate value". In a startup environment I think these is a critical workflow.