We started migrating some of our internal tools to https://ui.shadcn.com/ . We did not want to reinvent the wheel because it would take too much effort (and we did try a couple times in the past and we failed). It's easy to customize a shadcn theme for your own brand and you can integrate with Figma to collaborate with designers. If you are a small startup with less than 20 developers, I would probably use this or another "ready to use" UI components library. Else it may become a distraction from your main objectives. Note: Our audience is mostly B2B so our users are not too picky on the design/UI part of the product.