Why expired deal pages stay online
Expired offers are clearly marked and kept for price context, never to farm clicks.
When an offer ends, its page does not vanish. It switches to an expired state: the banner says the offer has ended, the buy button is removed, and any old code is marked as unreliable.
Why keep the page
Deal pages accumulate price history. Knowing that a product sold at a given price last month is exactly the context you need to judge the next promotion, and deleting the page would throw that away.
What changes on expiry
The offer leaves all current listings and feeds immediately, the purchase link is disabled, structured data stops advertising an active offer, and the page points to current alternatives from the same brand or category instead.
What we do not do
We do not leave dead codes looking active, redirect expired pages to unrelated offers, or keep pages that have neither history nor a current alternative - those are removed from the sitemap and eventually retired.