An image without alternative text is skipped by a screen reader or read out as the filename, something like "IMG_4021.jpg" or "product-photo-3". For a visitor who browses non-visually, this means that information that is self-evident to other visitors — what is in the photo, what an icon means, what a button with only a pictogram does — is simply absent. This is exactly what the success criterion on text alternatives in WCAG 2.1, and with it in EN 301 549, seeks to prevent.
The direct consequence is thus functional: some of your visitors miss information or cannot complete an action. The indirect consequence affects your documentation. Missing alt text, if present on your site, belongs in your own assessment and in the accessibility declaration as an open point. If you do not do this, then the declaration does not match reality, and that is something different from not having solved the problem itself — it is a declaration that does not reflect the facts.
Why this is so often overlooked
With many webshops and CMS systems, an image is automatically published as soon as a file is uploaded, without a required field for a description in between. Product photos, icons in the footer, buttons that consist only of a pictogram: these are all places where alt text is easily forgotten, precisely because the image works fine for a sighted visitor. This does not make the issue less relevant, but it does explain why it occurs so often.
What practically goes wrong for visitors
It affects not only people who use a screen reader. Search engines read alt text to determine what a page is about. Visitors with a slow connection who have images turned off see the alt text instead. And at a checkout step where product images are the only indication of colour or variant, missing or meaningless alt text is not cosmetic but functional: someone cannot then determine with certainty what they are ordering.
The limit of an automated scan
An automated test can determine whether the alt attribute is present and whether it is empty. That is useful, but it is not the same as determining whether the text is substantively correct. "Image" or the filename as alt text counts technically as present, but tells a user nothing. That distinction — present versus meaningful — requires assessment by a human, and that is precisely why every report from axessia.eu states which part of the test was performed automatically and which part was not. If you want to know how that test is structured, you can read that on the page about how our testing works.
What this means for your declaration and your action list
Missing or meaningless alt text, if you find it, belongs in your action list with a realistic estimate of what is needed to supplement it. This is usually not technically complicated work, but it is work that must happen consistently: with every new product photo or new icon again. An improvement plan that names this point and sets a date when it is resolved is something different from a declaration that leaves the issue unmentioned. An overview of what should be in such a plan, and how you demonstrate that, can be found in the knowledge base by topic.
Who looks at this
This is substantively one of the easiest points to determine objectively: an image either has an alt attribute or it doesn't, and the text is either meaningful or it isn't. This makes it a point that is relatively quick to spot in the event of a complaint from a user or during a review by a market surveillance authority, simply because it requires little interpretation. What a market surveillance authority does with this varies by country and by situation, and axessia.eu makes no prediction about that; for the competent authority and the procedure to follow in your country, we refer you to the official information on this.
If you want to see whether this type of issue occurs on your own site, that's a good starting point: it's precisely the kind of finding that a quick-scan already makes visible. The full scan including the checkout process and the login flow, the report in plain language and the statement itself are part of the paid service; what that costs is shown on our pricing page. Start with no obligation with the free quick scan of a few key pages to see where you stand now.