Remember it's probabilistic, not certain. There are still companies out there where you'll get hired with just a casual 30 minute conversation about your past work and how it should help you deliver value for this new work, maybe even over lunch. Different companies, even different teams or interviewers within companies, will have their own criteria with their own quirks and sometimes mental games. Even with perfect preparation on the technical side, you can easily fail a process because you failed some mind game, and those you can't really grind for. In other words, accept that no matter how much you prepare there's still a significant chance at failure, and use that to forgive yourself for not spending all your time trying to be in a constant state of readiness and trying to minimize a small portion of that chance, and maybe chill out some.