"Two waves of indexing" — Google's Martin Splitt now calls it an oversimplification; "pretty much every website, when we see them for the first time, goes to rendering" and the waves "play less and less of a role"

Claim: The "two waves of indexing" model — index raw HTML first, render JS later in a "second wave" that could lag days/weeks — was widely repeated in SEO circles from a 2018 Google I/O talk. Google itself now disowns it as an over-simplification.

Martin Splitt, who helped present the original model:

"That was an oversimplification… it implied a bunch of stuff that were not meant to be implied."

In a 2019 Zürich discussion he said the two waves "play less and less of a role," that "pretty much every website, when we see them for the first time, goes to rendering," and that rendering is cheap enough that even non-JS pages pass through it. He stopped short of declaring it dead and said crawling/rendering/indexing would eventually "come closer together."

Source: Martin Splitt (Google), 2019 Zürich SEO discussion and subsequent commentary.

Confidence: High (direct Splitt quotes).

Caveat: "Two waves" is still a useful mental model for explaining why JS content can lag, but it is no longer an accurate literal description of Google's pipeline. Do not use it to claim "JS content takes a week longer to index" as if it were a hard rule. See Rule: do not present "two waves of indexing" as a literal current model — Google itself has called it an oversimplification; use it only as a teaching aid for why JS content can lag.