Buried deep in a technical article is confirmation of something that we have known for a long time – the number of watchers you have makes your listing appear more valuable to eBay’s search engine, Cassini. A recent article promoting the eBay development system confirms that having many watchers is a metric that eBay pays attention to – which makes sense as generally speaking more watchers means more interest and more potential buyers.
This is why it’s worth factoring in the number of watchers when deciding whether or not to end a slow selling listing. It does make a small difference to search placement, and it is possible to buy watchers through sites such as Fiverr. However this is not recommended – eBay is wise to these sort of Black Hat practices and it’s possible they will punish a suspicious amount of sudden watchers by pushing listings down search results.
The original article here: https://partnernetwork.ebay.com/epn-blog/2018/5/meet-the-merchandising-api-your-gateway-to-higher-revenue-per-conversion