Analysis
The quote "The biggest risk is not taking any risk… the only strategy that is guaranteed to fail is not taking risks" is correctly attributed to Mark Zuckerberg and appears in a video of his talk at Y Combinator's Startup School. However, the talk took place in 2015, not 2017. The statement misstates the year while correctly naming the speaker and venue.
Background
Mark Zuckerberg delivered a keynote at Y Combinator's Startup School in August 2015, during which he emphasized the importance of taking risks for entrepreneurs. The quote has been widely circulated online, often without precise citation of the year. No record exists of a similar keynote by Zuckerberg at Y Combinator in 2017.
Verdict summary
Zuckerberg did say the quoted words, but not at a 2017 Y Combinator Startup School keynote.