Questions · Evaluate
Is missing variant data the same as a broken size picker?
No, and the difference matters. This is about whether the options are described in the data. A hover only variant picker is about whether an option that is described can actually be chosen, and it stops the journey later, at the buy stage.
Why it happens
Shopping instructions are usually specific. A shopper asks for a size, a colour, a capacity. A product page that presents one price and one availability for a grid of twenty combinations forces the agent to guess which of those facts applies to the combination in question.
Guessing here is unusually costly, because a wrong answer about size availability produces a failed purchase rather than a mild disappointment. Agents avoid it by preferring stores that state the grid.
This comes up at the Evaluate stage. The full treatment, including how to reproduce it and what to change, is on Variants are not described in structured data.
Related questions
Run a free scan and find out which of these your store actually hits.