When you have video content.
WHERE VIDEO HELPS
Keeping visitors on a page longer Answering questions better than text for some topics Appearing in video results Being findable on video platforms, which are themselves search engines
HOSTING IT
Do not host video files on shared hosting. They consume enormous bandwidth and serve slowly.
Use a video platform and embed. It is faster for visitors, cheaper, and makes the video findable on that platform too.
OPTIMISING THE PLATFORM LISTING
A descriptive title using the words people search A full description with links back to your site Relevant tags A custom thumbnail Captions, which are indexable and serve accessibility
ON YOUR OWN PAGE
Surround the embed with text covering the same topic. Engines index the text, not the video content.
A transcript is genuinely useful: it serves people who cannot watch, and it gives engines substantial relevant content.
STRUCTURED DATA
Video markup can produce enhanced results with a thumbnail.
PERFORMANCE
Embeds are heavy. Load them only when needed rather than on initial page load.