Recruitment will go wrong sometimes, there's no guaranteed way to prevent that. As companies get larger the chance of getting somebody on the team, with whom's interview you weren't involved, gets higher. Sometimes you just have to make the best of these bad situations.
I'm not saying you shouldn't try to fix the hiring problem, just that if something goes wrong try to fix it as much as possible with onboarding, via mentoring.
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Recruitment will go wrong sometimes, there's no guaranteed way to prevent that. As companies get larger the chance of getting somebody on the team, with whom's interview you weren't involved, gets higher. Sometimes you just have to make the best of these bad situations.
I'm not saying you shouldn't try to fix the hiring problem, just that if something goes wrong try to fix it as much as possible with onboarding, via mentoring.