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Re: Clarification of WCAG intent and meaning of techniques [Re: WCAG considering amending F65 to NOT fail missing ALT text if title or aria-label is present]

From: Detlev Fischer <detlev.fischer@testkreis.de>
Date: Wed, 27 Nov 2013 22:23:24 +0100
Cc: David MacDonald <david100@sympatico.ca>, 'Janina Sajka' <janina@rednote.net>, 'HTML Accessibility Task Force' <public-html-a11y@w3.org>, WCAG WG <w3c-wai-gl@w3.org>, public-comments-wcag20@w3.org, 'Gregg Vanderheiden' <gv@trace.wisc.edu>, kirsten@can-adapt.com
Message-Id: <3DB63386-1997-4D25-8FD6-DB2B4009EDD7@testkreis.de>
To: Michael Cooper <cooper@w3.org>
Hi Michael,

you add an important perspective here which I might have picked up had I followed WCAG WG deliberations more carefully. 

I have so far assumed that the sole purpose of re-working Techniques like F65 in preparation of publishing ARIA Techniques was to ensure that if a tester still detected a failure after running through the re-worked test, it would be crystal clear that the content fails the SC. And I believe James Nurthen has followed the same assumption in his line of argument. 

If it is always possible to meet the Success Criteria in some other way despite hitting a Common Failure, any fine-tuning (and thereby complicating and softening) of individual Failure techniques seems pointless. The Common Failures would loose the special status they had in comparison to the Sufficient Techniques with their known disclaimer. Why keep Failure Techniques that do not show how to do it right, and can never be used to prove conclusively that something was done wrong (i.e., fails)?


On 27 Nov 2013, at 21:03, Michael Cooper wrote:

> I thought it would be helpful to clarify what the WCAG Working Group is considering and its reasons for asking the question that started this thread.
> To recap background on the structure of WCAG 2.0 and its supporting materials: The Web Content Accessibility Guidelines 2.0 defines normative requirements for accessible content. This means that an author wishing to claim conformance to WCAG 2.0 must ensure their content meets the Success Criteria. The WCAG 2.0 Success Criteria are abstract, though, so they are supported by informative resources including the WCAG 2.0 Techniques. Informative resources provide interpretive guidance from the WCAG Working Group, and Techniques suggest how the Success Criteria might be met in particular technologies. But these are only informative suggestions, and it is possible to meet or fail to meet the Success Criteria without matching the patterns suggested in the techniques.
> The same is true of Failure Techniques. These describe authoring practices that might cause a page to fail the Success Criteria. But these, too, are informative, and it is possible to fail the Success Criteria in other ways, or to use patterns that match a failure technique but do not in fact cause the page to fail because another technique was used that caused the page to pass. In fact, as time passes, the Working Group has become more and more concerned that some of the failure techniques no longer describe situations that always fail, due to changes in technology. The group is now trying to identify and update some of these techniques.
> This brings me to the technique at question in this thread, "F65: Failure of Success Criterion 1.1.1 due to omitting the alt attribute...". This technique says it is a failure of WCAG 2.0 if the alt attribute is omitted on certain elements, because text alternatives would not be available. Since the time that technique was written, new approaches to associating text alternatives have become available, for instance aria-label and aria-labelledby among others. While there are concerns about how widely implemented these are and if they fully fulfill the role of alt, it seemed to the Working Group that it would be worth updating the failure to reflect new technology, so it would not indicate that content fails when it may not.
> There are many considerations to making a change like this. Although failure techniques are only informative, the goal is to make them as accurate as possible to the technologies of the time. But as we all know, there is not consensus in the accessibility community about whether newer technologies are an acceptable replacement for alt, for both technical and strategic reasons. The WCAG WG did not want to make a change to the technique that is not in line with the consensus of the HTML Accessibility Task Force which has worked most closely within W3C on this issue. This is the reason that the group brought the question to this forum.
> The purpose of all this background is to clarify the intentions and plans of the WCAG Working Group. The goal is to coordinate and make sure the group takes an action that is accepted in the accessibility community, rather than make one decision within the WCAG Working Group that it knows might not be accepted by many other stakeholders. The group wants to understand the variety of perspectives and does not intend to make a hasty or one-sided change. It seems, though that some update to the failure technique is needed, although it could turn out after this exploration that the consensus is not to change the technique. Even after the group makes a proposed change, if any, to the technique, there will be further rounds of review - in context of a draft of the technique at that point. And in the end, the technique is still non-normative - other organizations are free to disagree with it and follow other approaches to meet WCAG 2.0.
> I hope this helps people understand the intent of the message that started this thread and what the WCAG Working Group does and does not plan to do.
> Michael
> On 22/11/2013 6:27 PM, David MacDonald wrote:
>> On behalf of the WCAG working group, I have an action item to solicit
>> responses from the wider community regarding a proposed amendment to WCAG
>> failure technique F65 regarding missing ALT. Currently; if an <img> element
>> is missing from an ALT attribute the page fails WCAG SC 1.1.1 Level A. Some
>> are proposing that we allow authors to use the aria-label, aria-labelledby,
>> and title attributes INSTEAD of ALT. 
>> So under the amended failure technique NONE of the following would fail
>> WCAG:
>> <img src="../images/giraffe.jpg" title="Giraffe grazing on tree branches"/>
>> <img src="../images/giraffe.jpg" aria-label="Giraffe grazing on tree
>> branches"/>
>> <img src="../images/giraffe.jpg" aria-labelledby="123"/>
>> <p id="123"> Giraffe grazing on tree branches</p>
>> As you can imagine there are strong opinions all around on this so I
>> suggested we get a sense of what other groups such as the HTML5 A11y TF and
>> PF think.
>> Those in favour of the change provide the following rational: 
>> --These alternatives on the img element work in assistive technology
>> --The aria spec says these attributes should get an accessible NAME in the
>> API  
>> http://www.w3.org/TR/wai-aria/roles#textalternativecomputation
>> --They say it's easy to teach beginner programmers to just always use an
>> aria label on everything, rather than requiring a label on form fields and
>> alt on images
>> --They feel as a failure F65 is very strong if fails a page for missing ALT,
>> especially if other things work, and they would like to soften it to allow
>> other things that work.
>> --html 5 allows a <figure><legend> combination instead of alt, so they feel
>> WCAG will have to change F65 anyway to allow a figure with a legend, and
>> that helps open the door to this discussion
>> Those in favour of the status quo (which fails missing alt text) provide the
>> following rational:
>> --aria-label, labelledby and title, are not really suitable attributes for
>> img alternative text because they implies a label or title, rather than an
>> alternate text, so it is not a semantic equivalent
>> --title is not well supported
>> --some feel that the aria spec is not in any way suggesting these as
>> replacements to ALT.
>> --aria instructs authors to use native html where possible, and they could
>> not come up with viable use cases of omitting alt text
>> --there are hundreds of millions of dollars invested in current evaluation
>> tools, and methodologies, and this would represent a major departure from
>> one of the most basic accessibility convention, that is almost as old as the
>> web and is the "rock star" of accessibility
>> --it could cost a lot of money to change guidance to developers etc..., and
>> muddy the waters on a very efficient current evaluation mechanism
>> --when the figure/legend is supported by AT we can amend F65 but that is a
>> different issue and the semantics of this construct are OK for text
>> alternatives, rather than the label/labelledby/title options
>> --it may cause some confidence problems to WCAG legislation, because it
>> represents a strong loosening to a fundamental Success Criteria, an
>> unnecessary change that doesn't help the cause of accessibility, but just
>> complicates things
>> --ALT is better supported and the text appears when images are turned off.
>> --initial twitter feedback from the community is strongly against changing
>> this failure
>> There are probably other reasons on both sides which we hope to hear ... but
>> these should start it off. Please give your opinions and reasons.
>> Current technique here:
>> http://www.w3.org/TR/WCAG-TECHS/F65.html
>> Proposed failure here (see test procedure)
>> Cheers,
>> David MacDonald
>> CanAdapt Solutions Inc.
>> Tel:  613.235.4902
>> http://ca.linkedin.com/in/davidmacdonald100
>> www.Can-Adapt.com
>>   Adapting the web to all users
>>             Including those with disabilities
> -- 
> Michael Cooper
> Web Accessibility Specialist
> World Wide Web Consortium, Web Accessibility Initiative
> E-mail cooper@w3.org
> Information Page

Detlev Fischer
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Received on Wednesday, 27 November 2013 21:10:54 UTC

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