Evaluation and feedback

Judging a person, a piece of work or a candidate: the shortcuts that distort judgement.

Evaluating a person, a piece of work or a candidate means comparing, remembering and summarising: three operations where the brain's shortcuts creep in. First impressions, the latest events, resemblance to oneself, comparison with the previous candidate colour judgement without our noticing.

Countermeasures are procedures: criteria written before the evaluation, facts recorded over time, structured interviews, cross-checked opinions. A possible starting point: the halo effect.

The halo effectOne visible quality colors judgment about everything else. Where it hits (recruiting, evaluation, promotions, vendor selection), how to spot it and contain it with separate criteria.The recency effectWhat happened most recently carries more weight than what happened before. Where it strikes (annual review, project retrospective, panel, memory of a meeting), how to spot it, and how to counterbalance it with ongoing tracking.The primacy effectThe first information received carries more weight than what comes after and colors overall judgment. Where it strikes (recruiting, onboarding, first code review, first incident), how to spot it, and how to defend against it.Similarity BiasWe prefer, hire, and promote people who are like us, believing we're judging their competence. Where it hits (hiring, promotions, team building, reviews), how to spot it and contain it.The fundamental attribution errorWe explain other people's behavior by their character and our own by circumstances. Where it strikes (feedback, evaluation, incident reviews, conflicts), how to spot it, and how to correct it by looking at the situation first.Negativity biasNegative information carries more weight than equally strong positive information in our judgments, memory, and decisions. Where it hits (feedback, incident reviews, team climate), how to spot it, and how to rebalance.The contrast effectWe judge a person, an offer, or a piece of work by comparing it with what was just seen, not in absolute terms. Where it strikes (back-to-back interviews, application screening, reviews, estimating), how to spot it, and how to evaluate against a rubric.The mere-exposure effectWhat we encounter often ends up pleasing us and inspiring trust, for no real reason. Where it strikes (choice of suppliers and tools, promotions, assigned tasks), how to spot it and how to offset it.The Goodhart effect (visibility bias)We value what can be measured and seen; as soon as a measure becomes a target, it stops measuring well. Where it strikes (indicators, goals, bonuses, dashboards, velocity), how to spot it, and how to choose measures that hold up.The manager's Dunning-KrugerThe manager overestimates their ability to judge a technical domain they no longer practice. Where it shows up (trade-offs, estimates, architecture choices, expert evaluation), how to spot it, and how to correct it without losing legitimacy.