How to un-bug your application

It's probably a professional bias, but I notice bugs A LOT . And often they prevent me from using some software. Last week, I wanted to shop for some clothes online and spotted several bugs in key functionality, and one of them was critical. The support chat window was buggy, the page with size tables shows plain HTML, and the most ridiculous - I wasn't able to submit a purchase, because adding an address endpoint returns 500. And it was a world-famous brand. The support asked me to send them my