The Business Insider IGNITION conference was a reunion of sorts, at least for Drew Houston, co-founder and CEO of Dropbox, and Paul Graham, co-founder of Y Combinator and the first investor in Dropbox. Business Insider US Editor-in-Chief Alyson Shontell moderated the discussion. In addition to memories from the YC process, Drew and Paul shared insights into scaling companies, turning ideas into a business, and preserving innovation. Drew said, “You can't fake growth. [Growth] is just a measure of, ’Do you have customers? Are they happy?’“ Learn about the growth mindset and more from Drew and Paul in the full conversation here.