What should happen to out-of-stock and discontinued product URLs so SEO value is not destroyed?

Handle the URL according to the product's expected future and whether a real replacement exists.

For temporary stockouts, keep the product URL live if the product is likely to return. Clearly show availability, preserve useful specifications/reviews, offer notifications, and link to relevant alternatives. Keep structured data availability accurate.

For permanently discontinued products with a true successor that satisfies the same intent, a targeted 301 can be appropriate. The replacement should be genuinely equivalent—not merely any product in the same category.

When there is no close replacement, consider keeping a useful discontinued page for a period if users still search for manuals, specifications, compatibility, support, or historical information. If the page no longer serves any value, return 404/410 rather than redirecting it to an unrelated category/homepage.

Update internal links, category listings, recommendations, and XML sitemaps so retired products are not repeatedly promoted as active inventory.

Preserve inbound-link value thoughtfully. A page with substantial external references may justify a richer archive/replacement experience rather than immediate deletion.

For seasonal products, avoid treating predictable temporary absence as permanent retirement.

The mistake is using one rule for every inventory state. Product lifecycle should be modeled explicitly so users and search engines receive an honest, stable response.