What was your most embarrassing moment working on your project?

I'll start with mine. I'm currently near the end of developing a mobile app called Tip Buddy that will be the world's first automated gratuity calculator powered by computer vision. Basically the user can point the camera of their phone to the bill total and click on a button to automatically calculate the tip and total from thebl image. The app also allows users to split a bill both equally and proportionally. I had the "brilliant" idea of building a network effect into this app by adding a Venmo button at the end of the calculation step for splitting the bill. My theory was that I could have my users Venmo request their friends right from the app and it would send a custom message that they used Tip Buddy to send the request. This would leverage Venmo as both a payment platform as well as a social media platform for free advertising where others would hopefully FOMO into trying to Tip Buddy as well. This idea sounds cool on paper but when I got to developing the feature I realized my critical mistake. It turns out Venmo has closed their API since 2016 and no new developer accounts can be created. Oops! 😅