Gave a recommendation to the boss to do a thing. He said “Go and do the thing.” I wanted to do a proof of concept but there was no time. We got the contract. I tried to do the thing. It didn’t work. It WON’T work because the vendor’s marketing far overpromises what the product can do. No way to back down because the client is already fully invested in the solution. I want to quit my job AND my career now because I apparently suck at all of it.