Handle Out-of-Stock Product Pages
From an SEO standpoint, it's essential that out-of-stock pages continue to rank, both for consumers and retailers, but in the short-term, the experience is also frustrating for consumers and can drive them to other sites.
Is this a technical SEO problem?
The short answer is: not really. We want these pages to continue to rank — they're just not very useful in the short-term. Let's take a quick look at the usual toolbox to see what applies.
1: 404 (Not Found)
This one's easy. Do not 404 these pages. These products are coming back and you want to sell them. What's more, you want to be able to act quickly when they're back in stock. If you remove the page and then put it back (and then, most likely, remove it again and put it back again), it can take Google a lot of time to reconcile those signals, to the point where the page is out of sync with reality. In other words, by the time the page starts ranking again, the product might already be out of stock again.
2: 301 (Permanent Redirect)
As tools go, 301s still have a special place in our tool belts, but they're not a good bet here. First, the product still exists. We don't really want to move it in any permanent sense. Second, reversing a 301 can be a time-consuming process. So, just like with 404s, we're likely to shoot ourselves in the foot. The only exception would be if a product went out of stock and that prompted the manufacturer to permanently replace it with a similar product. Let's say Acme Essentials ran out of the 10-ounce Mountain Fresh hand sanitizer, so decided just to do away with that product and replace it with the 12-ounce option. In that case, by all means 301-redirect, but that's going to be a fairly rare situation.
3: 302 (Temporary Redirect)
This has got to be the one, right? Unfortunately, we're still stuck with the timing problem if this product comes back in stock for a short period of time. Let's say you're out of the Acme Essentials 10-ounce Mountain Fresh, but you've got the Trapper Moe's 10-ounce Spring Breeze in stock. Could you temporarily swap in the latter product from a search perspective? Maybe, if you could get the timing right, but now imagine the visitor experience. People would potentially still be able to search (on-site) for the Acme Essentials product, but then would be redirected to the Trapper Moe's product, which could seem deceptive and is likely to harm conversion.
4: ItemAvailability Schema
You can use the [availability] property in product-offer schemas to set options including: InStock, InStoreOnly, OutOfStock, and SoldOut. Google may choose to display this information as part of your organic result, such as this one (thanks to Claire Carlisle for this great example): Good news — sloths are still in stock. Unfortunately, there are two challenges to this approach. First, while searchers may appreciate your honesty, you may not be keen to display "Out of stock" on your search result when everyone else is displaying nothing at all. Second, we've still got the timing issue. You can automate flipping from "In stock" to "Out of stock" in real time, but Google still has to crawl and update that information, and that takes time.
Courtesy & Copyright
https://creativesaints.com/
http://graphicwebdesign.in/
https://www.papeel.com.br/
https://moz.com/blog/best-free-seo-tools
https://justcreative.com/2016/09/26/10-essentials-of-a-high-converting-landing-page/
https://justcreative.com/blog/page/50/
https://moz.com/blog?page=10
https://moz.com/blog/how-to-handle-temporarily-out-of-stock-product-pages