If you are a company using this technique for hiring – and you're not providing feedback – STOP.

If you and your team cannot suss out someone's capabilities from their CV, portfolio, interview, and references then YOU SHOULD NOT INVOLVED IN THE HIRING PROCESS.

It's a shit-test that you believe helps filter out under-qualified/unmotivated candidates, but it actually has the opposite effect:

Experienced candidates (you know, the ones you actually want at your company) just move on to lower-friction interviews where they don't have to start jumping through nonsensical one-way value exchanges on Day 0.