1. Discover and Crawling are two different things, they do not guarantee Indexing.
2. Crawling and rendering your published post is an instantaneous process done by the Google crawler, however, indexing may take hours, or even days sometimes.
3. Seeing your page through the 'webcache' command doesn't mean Google has completely fetched all your page details.
4. To make a page ranked and indexed, Google requires all the essential detail in the form of images, text, js, css, unintentionally blocking them with robotstxt, which can create errors.
5. The 'IndexNow command only makes crawling possible and doesn't confirm the page's indexing chances.
6. Page Rank can observe certain changes owing to the rendered versions.
7. Google converts pdf or lotus files into HTML before indexing. (edited)