Crawling, indexing, migrations and site audits: the technical work that decides whether a page can rank at all.
Discovered, currently not indexed means Google knows a URL and has not fetched it yet. A backlog model shows when it is a crawl capacity problem and when it is Google deciding the URL is not worth the trip.
Index bloat measured in recrawl days rather than adjectives, with the four controls ranked by what each one actually stops, straight from Google’s documentation.
Site architecture is the link graph, not the folder names. What Google actually documents about crawlable links and URL structure, plus a click-depth table that tells you how deep your site is allowed to be.
Google has documented how to run A/B and multivariate tests without breaking its own rules, down to which redirect code to use. The harder problem is statistical: most site templates do not have enough pages to detect the effect sizes people claim to measure. Here is the compliance matrix and the arithmetic.
An orphan page is a URL nothing on your site links to. Google’s documentation is explicit about how it discovers URLs, and a sitemap entry is not the same thing as a link. Here is what the docs actually say, a worked 12,000-URL example with the arithmetic, and the seven-step audit that surfaces yours.
Five filters on forty categories can generate four and a half million URLs, and Googlebot has to crawl them before it can know they are worthless. Here is the combinatorial arithmetic, Google’s own words on why it hurts, and a matrix of the five controls showing exactly what each one does and does not do.
Google dropped rel=next and rel=prev years ago and most pagination advice never caught up. Here is what the current documentation says, the four patterns ranked by what Google can actually crawl, and the arithmetic that shows why canonicalising every page to page one quietly orphans your catalogue.
A permanent redirect tells Google to index the destination. A temporary one tells Google to keep indexing the source. Here is the documented difference across all five redirect status codes, the hop limits, and the migration failure a 302 produces.
Most robots.txt problems come from using it for a job it does not do. Here is Google’s own documentation on what a Disallow rule actually achieves, the response-code matrix that decides how your file is read, and the audit I run on it.
A rel=canonical is a hint, not a rule, and Google says so in its own documentation. Here is the signal hierarchy that decides which URL actually gets indexed, and the conflict matrix I use to find out why yours is being overruled.