| Older channels become less dependent on algorithmic recommendations. | not_currently_testable | low | 0 | — | 22 |
| Distribution happens in two phases — test (low impressions, narrow audience) then scale. | inconclusive | low | 0 | — | 22 |
| Videos with average view percentage above 50% receive sustained impression delivery. | inconclusive | low | 0 | — | 22 |
| Browse / Homepage impressions are weighted toward existing subscribers. | not_currently_testable | low | 0 | — | 22 |
| Browse pickups are more durable than Suggested-driven impressions. | not_currently_testable | low | 0 | — | 22 |
| Cards contribute roughly 1% of traffic. | not_currently_testable | low | 0 | — | 22 |
| Channel-page-driven views come from highly engaged viewers. | inconclusive | low | 0 | — | 22 |
| As library grows, Channel Page share of views falls. | inconclusive | low | 0 | — | 22 |
| Comments-per-view tracks audience resonance better than likes-per-view. | inconclusive | high | 0 | — | 22 |
| Comments are weighted more than likes by the algorithm. | inconclusive | low | 0 | — | 22 |
| High click-through-rate drives video success more than high retention. | disagrees | high | 4 | 2026-04-26 | 5 |
| Neither click-rate nor retention alone matters; the product (or geometric mean) does. | not_currently_testable | low | 0 | — | 22 |
| Channels publishing daily need pre-recorded inventory; those without it burn out. | not_currently_testable | low | 0 | — | 22 |
| YouTube's algorithm tests a video primarily in its first 1–3 days, after which performance is largely set. | inconclusive | low | 0 | — | 22 |
| Once 30 days post-publish, a video's daily view rate stabilizes and varies little. | inconclusive | low | 0 | — | 22 |
| Editing title or thumbnail post-publish kills momentum. | inconclusive | low | 0 | — | 22 |
| Videos with high end-screen click-through have higher overall retention. | not_currently_testable | low | 0 | — | 22 |
| End-screen impressions and clicks contribute 5–15% of traffic. | not_currently_testable | low | 0 | — | 22 |
| Viewers from external sites have the highest engagement rates. | inconclusive | low | 0 | — | 22 |
| Days to first 100 subscribers is the slowest sub-acquisition leg. | inconclusive | low | 0 | — | 22 |
| Performance trajectory of the first 10 videos predicts month-12 channel state. | not_currently_testable | low | 0 | — | 22 |
| A video's lifetime trajectory is largely determined by its first 24–48 hour performance. | inconclusive | low | 0 | — | 22 |
| First video's day-30 performance correlates with month-3 channel trajectory. | not_currently_testable | low | 0 | — | 22 |
| Publishing video N consumes impressions that would otherwise have gone to video N−1, slowing N−1's trajectory. | agrees | high | 5 | 2026-04-24 | 7 |
| The 0–15-second retention drop is the strongest single predictor of overall performance. | not_currently_testable | low | 0 | — | 22 |
| Hour-1 view rate predicts the video's lifetime performance. | not_currently_testable | low | 0 | — | 22 |
| Longer videos accumulate more total watch minutes per viewer. | inconclusive | high | 0 | — | 22 |
| Videos 8–10 minutes long perform best for ad revenue and watch time. | disagrees | high | 1 | 2026-04-14 | 17 |
| A new publish steals impression budget from the rest of the catalog. | agrees | high | 1 | 2026-04-14 | 17 |
| Channels with narrow topical focus outgrow broad-topic channels. | not_currently_testable | low | 0 | — | 22 |
| Titles with numbers (5 Ways… / 3 Things…) perform better. | not_currently_testable | low | 0 | — | 22 |
| Late-afternoon publishing optimizes day-0 reach. | inconclusive | low | 0 | — | 22 |
| Channels that post on a consistent cadence outperform those that don't. | inconclusive | low | 0 | — | 22 |
| Publishing too often cannibalizes per-video performance. | agrees | high | 5 | 2026-04-24 | 7 |
| Long gaps between uploads cause the algorithm to deprioritize the channel. | inconclusive | low | 0 | — | 22 |
| Titles ending in ? outperform on click-through rate. | not_currently_testable | low | 0 | — | 22 |
| Once a channel has 30+ videos, key ratios (CTR, AVD, sub conversion) settle. | inconclusive | low | 0 | — | 22 |
| High retention drives video success more than high click-through-rate. | agrees | high | 4 | 2026-04-26 | 5 |
| Videos with growing Search-source share over time become long-term assets. | inconclusive | low | 0 | — | 22 |
| Shorter videos accumulate more views than longer ones. | inconclusive | high | 0 | — | 22 |
| Most subscribers come from a few breakout videos, not from many videos contributing equally. | agrees | high | 1 | 2026-04-15 | 16 |
| Channels with more subs per view have more engaged audiences. | not_currently_testable | low | 0 | — | 22 |
| Subscribed-state viewers have higher retention than non-subscribers. | not_currently_testable | low | 0 | — | 22 |
| Day-0 traffic is dominated by subscribed-state viewers. | not_currently_testable | low | 0 | — | 22 |
| Suggested impressions reach mostly non-subscribed viewers. | not_currently_testable | low | 0 | — | 22 |
| Channels accelerate after 1,000 subscribers. | not_currently_testable | low | 0 | — | 22 |
| Renaming a video resets its testing cycle. | inconclusive | low | 0 | — | 22 |
| Most videos peak in their first three days. | inconclusive | low | 0 | — | 22 |
| YouTube ranks by session length, not per-video metrics. | not_currently_testable | low | 0 | — | 22 |
| Saturday and Sunday uploads get less engagement than weekday uploads. | inconclusive | high | 4 | 2026-04-22 | 9 |