FORTUNE - Justin McLeod, founder of Hinge, started the dating app while at Harvard Business School. Initially struggling to attract users, he bribed students with KitKats and managed to attract only a few dozen sign-ups daily. To fund the app, McLeod collected checks of $5K to $10K from anyone willing to invest. He even deferred a job offer from McKinsey with a six-figure salary to focus on Hinge, eventually turning it into a success. By 2015, Hinge raised $26M before being acquired by Match Group. Today, McLeod remains Hinge's CEO, with the app earning $396M in 2023. He advises Gen Z entrepreneurs to balance idealism with practicality, encouraging them to take action rather than overthink their career paths.