Designed for the Edges

All Sectors

• The Problem

  Inclusive design is frequently treated as an accessibility add-on — adjustments made for edge-case customers after the main product experience has been built. This produces two problems simultaneously: the standard journey remains optimised for a fictional average customer, and the adjusted journey for customers with additional needs becomes a second-class experience. Consumer Duty makes both a compliance issue. The FCA’s vulnerability guidance explicitly states that firms should anticipate the needs of vulnerable customers in the design of products and services, not retrofit accommodations afterward.

• The Pattern

  The structural move is to test customer journeys against edge-case users and extreme scenarios systematically — not starting from the edges but stress-testing against them to ensure the design does not break for atypical but foreseeable customers:

  Edge-case stress testing

  Before any journey goes live, test it with the customers who are hardest to serve: highest cognitive load, lowest digital literacy, most emotionally compromised, least stable circumstances. The test is not whether the journey works for them with adjustments — it is whether the primary journey works for them without adjustment. Where it breaks, that is a design flaw in the main journey, not an edge-case accommodation need

  Genuine alternative pathways

  Phone, paper, and assisted digital as real equivalents of the primary channel, not degraded fallbacks. Alternative pathways should offer the same functionality, the same information, and produce the same outcomes. If the phone journey cannot do what the digital journey can, it is not an alternative — it is a lesser service

  Brief-stage inclusion

  Inclusive requirements must enter the product development process at the brief stage, not the QA stage. If vulnerability testing only happens after the product is built, the structural decisions have already been made and only surface-level adjustments remain possible. The brief should specify who the edge-case users are and what success looks like for them

• Indicators It's Working
  • Customer understanding scores for complex product features are comparable across customer segments — not materially worse for older, less digitally literate, or financially stressed cohorts

  • Alternative pathway usage is monitored and iterated with the same frequency as the primary digital channel

  • New product briefs include an inclusive design requirement and edge-case testing plan before development begins

  • Complaint and query themes related to confusion or inaccessibility decline across all segments, not just those flagged as vulnerable

• In Practice

  • A health insurer stress-tested its claims notification journey with customers over 75 and found that the digital form required 23 separate inputs across 7 screens, with no save-and-return functionality. Customers in this cohort abandoned at a rate three times higher than average — and most of them did not complain; they simply called. The call handler then completed the same form on their behalf. They redesigned the primary journey to reduce inputs to 12, added save-and-return, and introduced a progress indicator. Abandonment rates fell across all age groups, not just the cohort they had tested against. The edge case had revealed a flaw in the main design.

  • A motor insurer discovered that its renewal journey assumed continuity: same vehicle, same address, same circumstances. Customers whose circumstances had changed — a move, a health condition, a change in employment — had to call to update their policy before renewing online. For customers with cognitive impairment or communication difficulties, this created a barrier that effectively prevented renewal. They redesigned the renewal flow to surface and accommodate common life changes within the digital journey. The change improved completion rates for all customers and eliminated a complaint category that had been invisible because the affected customers had simply lapsed.

• Watch-Outs
  Common failure modes

  The failure mode is treating inclusive design as a checklist — producing a list of accessibility features that satisfies a review process without changing the underlying design logic of the primary journey. A second is treating it as a one-time exercise at product launch rather than an ongoing discipline: journeys that worked inclusively at launch can drift as they are iterated without vulnerability considerations maintained. A third is testing only within the firm’s existing customer base, which self-selects for people who could already navigate the journey — the customers excluded by the design are not available to test it.