95%-ile isn't that good (2020)
The post argues that "95th percentile" performance, while often used as a benchmark, is actually not an exceptional standard in many contexts. Using examples from software engineering, the author demonstrates that what is considered "good" at the 95th percentile can still be far from true excellence when compared against absolute scales or more demanding thresholds like the 99.9th percentile.
Background
Dan Luu is a well-known computer engineer and writer whose blog posts on software engineering, performance, and systemic risk are widely circulated in tech circles. This post pushes back against a common belief in tech companies that being at the 95th percentile of skill (i.e., better than 95% of peers) is excellent. Luu argues that in many competitive contexts — hiring, funding, startup survival — the cutoff for success is far higher, often at the 99.9th percentile or beyond, because the distribution of outcomes is extremely top-heavy. He illustrates this with examples from Y Combinator startups, elite college admissions, and professional sports. The piece is a sobering reality check for engineers who think "good enough" is safe, popular during the 2020 tech boom when many companies were hiring aggressively and engineers had high leverage.