Keep the selected variant truthful when it cannot be bought
Distinguish a sold-out variant from a nonexistent combination, unpublished variant, or inventory-location problem.
Skip this if Products with no variants
When a shopper selects a size and color, the page must keep talking about that exact combination. Quietly switching to an available variant can change price, media, subscription eligibility, SKU, delivery, or inventory while the interface still looks selected.
The decision is how each unavailability state should appear and what action it permits. Do not reduce every case to “sold out.”
The rest of this lesson is available once the Atlas is unlocked.