Complex or inaccessible language
Cancellation consequence written in legalese
A fictional service describes the effect of cancellation through a 220-word clause containing undefined terms and cross-references immediately before confirmation.
Individual HTML example · Interface interference
Payment step changes language without warning
A fictional shop presents product and basket information in English but switches mandatory fee and return text to another language on the payment screen.
This is an original fictional comparison. It depicts no real business and is not a regulator finding, statutory category or legal safe harbour.
Payment step changes language without warning
A fictional shop presents product and basket information in English but switches mandatory fee and return text to another language on the payment screen.
Complete payment. Mandatory charge and return conditions appear only in an unexpected language.. Amount affected: $84. Pay $84. Pay $84 after review
Order summary in English. Price, charge and return conditions remain understandable at payment.. Amount affected: $84. Pay $84 after review. Pay $84. Payable total and selected items, expanded: The summary shows the line items and total before “Pay $84 after review” is activated.
Why the first version can mislead: The presentation changes what the user can notice or predict at the checkout decision. The problematic state shows: “Mandatory charge and return conditions appear only in an unexpected language.” Its influence should be tested by comparing the consequence and usability of “Pay $84” with “Pay $84 after review”. A customer may commit without understanding material terms that appear only at the last step.
What a fairer design does: Keep material information in the user’s selected language and clearly offer any necessary language change before payment.
Show annotated differences (4)
Potentially problematic version
- Mandatory charge and return conditions appear only in an unexpected language.Why this state matters: The presentation changes what the user can notice or predict at the checkout decision. The problematic state shows: “Mandatory charge and return conditions appear only in an unexpected language.” Its influence should be tested by comparing the consequence and usability of “Pay $84” with “Pay $84 after review”. A customer may commit without understanding material terms that appear only at the last step.
- Pay $84 after reviewReview prompt: Do “Pay $84” and “Pay $84 after review” receive comparable prominence and explain their consequences before activation?
Neutral alternative
- Price, charge and return conditions remain understandable at payment.Fairer design: Keep material information in the user’s selected language and clearly offer any necessary language change before payment.
- Payable total and selected items, expanded: The summary shows the line items and total before “Pay $84 after review” is activated.Review prompt: Compare the basket before and after the action, including total and line items; does the mutation satisfy “Locale mismatch or avoidable complexity is evidenced”?
Review questions (3)
- Do “Pay $84” and “Pay $84 after review” receive comparable prominence and explain their consequences before activation?
- Compare the basket before and after the action, including total and line items; does the mutation satisfy “Locale mismatch or avoidable complexity is evidenced”?
- What neutral rendering or comprehension result would falsify the classification, particularly in light of “user-selected alternate language”?
Complete practice context
How this example relates to Complex or inaccessible language
Material guidance is presented in a language or level of complexity that makes informed choice materially harder for the target user. This is a design and research taxonomy for learning and evidence review, not a statutory offence label or an automatic finding that an interface is unlawful.
The full guide explains inclusion and exclusion criteria, potential harms, fairer design, evidence questions and separate Australian legal information layers. The example page isolates one scenario so it can be shared and discussed without reproducing the complete library on one page.
Continue comparing
Related examples
Open this example
Bundled options
Ticket and travel pass presented as one package
A fictional ticket seller offers a concert ticket only through a control that also adds a city travel pass, although the travel component is separately deliverable and not required for entry.
Bundled options
Support and migration locked into one plan
A fictional service offers a core plan only as a bundle with premium support and data migration, while implying those extras can be removed later although no controls exist.
Sources and provenance for this example
Evidence base
Sources
- An Ontology of Dark Patterns KnowledgeGray et al.; ACM CHI 2024 · Secondary · checked 2026-09-14 · DOI 10.1145/3613904.3642436; arXiv:2309.09640
- Competition and Consumer Amendment (Unfair Trading Practices) Act 2026Federal Register of Legislation · Primary · checked 2026-09-14 · C2026A00064