Work samples, and what makes them persuasive
In several fields a portfolio decides more than a résumé does. The common failure is showing quantity instead of judgement.
A portfolio is evidence that you can do the work, which means a small number of pieces shown well beats a large number shown indifferently. Three or four complete examples with context generally outperform a dozen without.
Context is what makes a sample readable: what the problem was, what constraints applied, what you did specifically, and what resulted. A reviewer cannot infer any of that from the artefact alone, and inferring it wrongly is worse.
Work done for an employer or client may be confidential. Permission is worth asking for, and where it cannot be given, a sanitised version or an equivalent personal project usually serves. Publishing confidential material is a reason offers are withdrawn.
Where no professional work exists yet, a self-directed project built to a real brief demonstrates the same things. Volunteer work for a small organisation produces samples and a reference at the same time.
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