Decision Log

A decision log is the case study format that hiring managers actually finish reading. It functions as a detailed record of every major decision made during a design project from initial problem definition through post launch analysis. Unlike traditional formats that prioritize visual appeal the decision log prioritizes transparency into the designer's thinking process. It uses a strict six section structure that keeps the narrative focused and actionable. The opening two line pitch delivers the who what and so what in under 50 words so a recruiter scanning on their phone at 9 am understands the project instantly. The problem section follows with specific details pulled from real data such as the 23 percent cart abandonment rate mentioned in the design portfolio guide or the volume of support tickets logged in a particular quarter. It avoids vague statements like the UI felt confusing and instead says 41 percent of users over age 45 abandoned the form at the address validation step according to Hotjar recordings from March 2022. The approach section maps the path taken including research conducted with tools like UserTesting.com hypotheses formed constraints encountered such as a rigid brand system from the 2018 guidelines and the reasoning for each pivot. This is where you prove you can navigate real world messiness. The work section presents the artifacts in story order not polish order. It leads with rejected concepts research synthesis diagrams and early wireframes before showing final interfaces from Figma. Every visual includes a caption that explains the decision like This version tested a vertical stepper but A B testing with 450 users showed it increased completion time by 19 percent compared to the horizontal layout we ultimately shipped. The outcome section reports verifiable results. If you have numbers from Amplitude or Google Analytics use them. If not be transparent with notes like the account management team reported 30 percent fewer escalation emails in the two months after launch. The closing reflection section separates seniors from everyone else. It contains one tight paragraph on what worked what did not and what you would change. An honest reflection from a 2024 case study read We launched without testing the new flow on Android 12 devices which caused a bug that affected 8 percent of users. I would prioritize cross platform testing in week two on future projects. The entire log typically spans 800 words with 8 to 12 captioned images and reads in four to six minutes. This format directly supports the five project portfolio strategy. The flagship project gets the most detailed decision log. The collaboration case uses it to document trade offs with stakeholders at companies like OpenAI or Anthropic. The depth piece layers in technical decisions such as how you structured a design system with Tokens Studio for Figma in a 2023 project. The decision log is what makes a portfolio signal competence instead of just taste.

What it is not is everything most designers currently publish. It is not a screenshot gallery dressed up with trendy transition animations and buzzwords like human centered and delightful. It is not the 15 screen carousel that shows only final polished work without any context for why those pixels exist. It is not the self aggrandizing narrative that claims sole credit for outcomes that clearly involved a team of six. It is not the fictional account that omits all failed experiments and presents every choice as inevitable. It is not the 2500 word tome that buries the key insights on page four where no hiring manager will ever reach them. It is not the generic template copied from a Medium article in 2019 that every junior designer at Webflow seems to use. Those versions might win awards on Awwwards but they fail the 90 second portfolio test described in the article. Hiring managers at companies like Figma in 2024 close the tab because they learn nothing about how the designer will behave when the roadmap changes or when the CEO hates the color blue.

Consider this concrete example from Maya Patel senior product designer at Loom. For her flagship project in the 2022 portfolio she created a decision log for the video recording interface overhaul. The two line pitch read Overhauled the recording flow for Loom which had grown to 12 million monthly users. I led design collaborating with three engineers one PM and the growth team which increased completion rate from 67 percent to 89 percent. The problem section cited specific friction. Session recordings from FullStory showed users restarting the process 2.3 times on average because the microphone and camera permissions dialog interrupted the flow and the aspect ratio selector was hidden in advanced settings. This led to a 14 percent drop in shares to Slack and email. The approach outlined a two week research sprint with 18 Loom power users from companies like Notion and Airtable. Constraints included maintaining compatibility with the existing Chrome extension built in 2020 and not increasing bundle size. She tested three hypotheses one of which involved AI suggested titles that ultimately got cut for scope reasons. The work began with the process artifacts. An affinity map from Miro interviews revealed three distinct user mental models. Early Figma explorations included a floating action button approach that 7 out of 10 test participants found confusing. Captions explained each turn. We abandoned the timeline editor integration after engineering estimated it would take 11 weeks against our six week deadline. Final designs showed the simplified one click record button with inline permission handling. The outcome delivered hard metrics. Post launch data from June 2022 showed the completion rate jump to 89 percent and a 31 percent increase in daily active recording users. The sales team noted shorter sales cycles for the enterprise plan. In reflection Maya wrote The biggest miss was not including the marketing team earlier. Their feedback on shareability would have moved the social preview feature from phase two to launch. For the next project I will create a cross functional kickoff workshop in week one. This decision log was 1100 words and became the main reason she received inbound recruiting calls from both Vercel and Perplexity AI. A second example comes from the 2021 Brex invoice approval redesign where the decision log called out a rejected kanban layout after FigJam tests with finance leads from Ramp showed it increased errors by 27 percent on mobile.

Use decision logs when building portfolios aimed at senior roles where decision making is the primary evaluation criteria. They fit perfectly in the flagship the collaboration and the depth pieces of the five project model from the design portfolio paper. Deploy them when pitching to clients who have design maturity like those who already work with agencies such as Pentagram or IDEO. They work for internal presentations at product companies to justify design choices to engineering and product leadership. They shine in job interviews when you need to walk through past work in detail. They are essential when your work involves complex systems like enterprise SaaS tools built in 2021 to 2023 where trade offs dominate. Avoid decision logs for portfolios targeted at visual agencies or brand studios where the audience cares more about aesthetic sensibility than process. Skip them for junior positions where the bar is execution and tool proficiency rather than strategic thinking. Do not use them for projects that lack measurable outcomes or real constraints like most student work or pure passion projects without deadlines. Never deploy the format if you cannot include an honest reflection because a generic one reads as performance. The decision log demands real material to work with.

A decision log turns your portfolio from a vanity project into a compelling argument that you should be the next designer hired.