Nacho Analytics shows us that search engineers are helping Amazon get 600% more in sales than competitors.
Take away: investing in good search results costs money, but it's well worth it. If you have better search, you sell more.
What is a search relevance engineer? It's a technical person that helps ensure that what you search for you get. E.g.: if you're on a website and you search for "bat," do you get the sports instrument or the animal? Constantly honing and improving the search code creates residual improvement and a residual increase in sales.
Here is the Nacho article about Amazon:https://www.nachoanalytics.com/blog/amazons-growth-hack/