Ask HN: Who's using a third party company for tech screens? Is so, why?

I'm a Principal engineer at a FAANG company and been thinking about changing jobs. By all quantitative means, I am a good engineer, I have been promoted multiple times, had good feedback, and led several well-known successful projects for my employer. I don't interview well, it's nerves, in non-interview settings, I crush these problems, however once the timer is going and someone is watching, I panic, it's a character flaw.

I was recently cold-called on Linkedin and decided to give it a shot, since it was with a relatively large internet company. I was flippant and didn't do a lot of preparation. The company was using Karat.io to perform tech screens. I totally flubbed the tech screen, I've done over 350 interviews at my current employer and I've seen lots of folks melt down, it was heinous.

Normally, I could care less, I got good data points for myself out of the interview and I had already decided I didn't want the job, that's not why I continued. However, after performing badly, it hit me that I have potentially cut myself off from not only this job but employment at any future customer of karat.io.

I reached out to Karat and they assured me data is only shared with the target company and for the specific position. The disheartening part is that there is no limit on the amount of time they keep the data. All it takes is poor company performance, coupled with desperation, and suddenly in the future they could offer a "pre-screen" service, where they screen candidates for you based on their past interview performance. I am at the behest of the scruples of all future executives of karat.io.

I have decided to refuse interviews with companies using a 3rd party screener on principle. I wonder, companies that are using these, why are you outsourcing potentially one of your most critical functions? If engineers do not conduct interviews, you will not build that expertise as an organization. Engineers at these companies, do you feel good with this practice?