The most arduous hiring processes are often little more than an illusion of selection, yielding a process that is more the rolling of dice. Most hiring processes hire based upon interview skills that have extraordinarily little correlation with job performance.

Google has such a famous interview process that everyone tries to clone it. For that they get employees with an average tenure of 3.2 years, made worse that internal project-to-project migration is endemic. They have a tiny core of institutional knowledge, and then a passing army of travelers.

This industry would be far more robust if it hired quickly and fired fast, because the only way you know how someone will do in the role/team/org is by actually having them in the role/team/org. Everything else is just loose proxies that do little. Iterate through people and just punt out the ones that don't work. That shouldn't be a big deal.