Even the best hiring processes produce occasional mistakes. The engineer who interviewed brilliantly may struggle to deliver in the actual role. Recognising and addressing a hiring mistake quickly and humanely is a critical skill for engineering managers. This guide walks you through the assessment, support, and decision-making process.
Recognising a Hiring Mistake Early
A hiring mistake becomes apparent when a new engineer consistently fails to meet the expectations of the role despite receiving appropriate onboarding and support. The key word is 'consistently' — every new hire has an adjustment period, and it is normal for output to be lower during the first few weeks.
Warning signs typically emerge within the first sixty to ninety days. The engineer struggles with tasks that should be straightforward for their level. They repeatedly need hand-holding on problems their interview performance suggested they could handle independently. Their code quality, communication, or collaboration patterns are significantly below what you expected.
Be honest with yourself about what you are observing. Managers often rationalise early warning signs because admitting to a hiring mistake feels like a personal failure. It is not — hiring is inherently uncertain, and even the most rigorous processes have a significant error rate. The failure is not in making the mistake; it is in ignoring the evidence.
Assessing Whether It Is Truly a Bad Hire
Before concluding you have made a hiring mistake, examine whether the problem might be environmental rather than individual. Is the onboarding process adequate? Has the new hire been given clear expectations and the resources to meet them? Are they working on tasks that match the role they were hired for?
Consider whether the engineer might be a strong performer in a different context. Some people thrive in structured environments but flounder in ambiguity. Others are excellent individual contributors but struggle on highly collaborative teams. A mismatch between the engineer and the specific team or role is different from a fundamental inability to perform.
Seek input from others who work closely with the new hire. Your perspective alone may be incomplete or biased. Ask their onboarding buddy, their tech lead, and engineers who have reviewed their code. If multiple people share your concerns, the evidence is stronger. If others see strengths you have missed, you may need to adjust your expectations.
Supporting the New Hire Before Making a Decision
You owe the new hire a genuine effort to help them succeed before concluding they cannot. This means providing direct, specific feedback about where they are falling short and what improvement looks like. Many new hires who struggle initially can succeed with the right support — clearer expectations, more structured tasks, additional mentoring, or a temporary reduction in scope.
Set a clear timeline for improvement — typically thirty to sixty days — with specific, measurable milestones. Meet weekly to review progress and adjust support as needed. Document these conversations and agreements so both of you have a clear record of the expectations and the effort invested.
Be transparent with the new hire about the situation. Saying 'I want to be honest that the transition has been harder than expected, and I want to work with you to close the gap' is more respectful than letting them flounder without feedback while you privately contemplate their departure.
Making the Difficult Decision
If the improvement period passes without meaningful progress, you need to act. Keeping a bad hire on the team too long is unfair to everyone — the struggling engineer, the team members who are compensating for them, and the organisation that is paying for a role that is not being filled effectively.
Work with your HR partner to understand your options. Depending on the jurisdiction and your company's policies, these may include extended probation, a performance improvement plan, a managed transition to a different role, or separation. In many organisations, addressing a hiring mistake during the probationary period is simpler and less adversarial than a later-stage termination.
Handle the separation with dignity. Regardless of how frustrated you are, this person took a job in good faith and is dealing with a difficult situation. Provide honest feedback about why it did not work out, offer whatever support your company provides (severance, reference letters, transition time), and treat them with the same respect you would want in their position.
Learning from the Hiring Mistake
Every hiring mistake contains lessons. After the situation is resolved, conduct an honest post-mortem on your hiring process. What did you miss in the interview? Were you testing for the right skills? Did you overweight a strong cultural fit and underweight technical ability, or vice versa? Were the interview questions representative of actual job demands?
Common patterns include overvaluing confidence in interviews, not testing for the specific technical skills the role requires, ignoring behavioural signals in reference checks, and hiring for potential without a realistic plan to develop it.
Share your learnings with other hiring managers in your organisation. Hiring mistakes are expensive — each one costs months of salary, onboarding investment, and lost productivity. The more the organisation learns from individual mistakes, the better the overall hiring process becomes.
Key Takeaways
- Look for consistent underperformance over sixty to ninety days, not isolated struggles during onboarding
- Assess whether the problem is the individual or the environment before concluding it is a bad hire
- Give the new hire direct feedback, a clear improvement plan, and genuine support before making a decision
- Act decisively if improvement does not materialise — delaying is unfair to everyone involved
- Conduct a post-mortem on your hiring process and share learnings with the organisation
Frequently Asked Questions
- How do I tell the team when a new hire does not work out?
- Be straightforward without sharing confidential details. Something like 'Alex has decided to move on, and their last day is Friday. I appreciate the support you all provided during their time here.' If the team asks for more detail, acknowledge that it did not work out without placing blame: 'It was not the right fit, and we have both learned from the experience.' Your team will respect your discretion and professionalism.
- Should I lower my standards to avoid firing a new hire?
- Absolutely not. Lowering standards to accommodate a bad hire degrades team performance, demoralises strong performers, and sets a precedent that mediocrity is acceptable. The compassionate response is not to pretend the problem does not exist — it is to provide honest feedback, genuine support, and, if necessary, a dignified exit. Keeping someone in a role where they are failing is not kind to them either.
- How do I prevent hiring mistakes in the future?
- No process eliminates hiring mistakes entirely, but you can reduce their frequency. Use structured interviews with consistent rubrics to reduce bias. Include a practical work sample or pair programming exercise to test real-world skills. Conduct thorough reference checks with specific questions about the candidate's performance in situations similar to your role. And involve multiple interviewers with diverse perspectives — the more eyes on a candidate, the less likely a significant weakness goes undetected.
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