Crawlability
Crawlability is how easily a search engine crawler can reach a page and read its content, governed by whether the page is linked, allowed by robots rules, served without errors, and rendered so its text exists in the HTML the crawler actually parses.
A page can be live for human visitors and still be invisible to a crawler. The crawler has to find a URL through a link or sitemap, be permitted to fetch it (robots.txt, the noindex directive, and HTTP status codes all decide this), and then extract real text from the response. If any of those steps fails, the content does not enter the index, no matter how good it is.
The rendering step is where modern stores quietly lose ground. Content injected by JavaScript after the page loads, such as a reviews widget pulled from a third-party script or an iframe, often is not present in the initial HTML. Some crawlers render JavaScript on a delay or not at all, so those reviews can be uncrawlable: the shopper sees them, the crawler does not. Iframes are a particular trap, since their contents sit on a separate URL and are rarely attributed to the host page.
The honest test is to fetch the raw HTML (view source, or a curl request) and search for the actual review text. If it is missing there, it is missing from the crawler view too. Getting existing reviews readable, corroborated, and cited by search and AI is the gap BetterReviews closes, by rendering that content server-side rather than leaving it locked inside a client-only script.