01When video is appropriate
Product demo, clear process, customer feedback, complex "how it works" service in 60-90 seconds.
02Machinery
Compressed MP4/WebM, poster as LCP, no auto sound, lazy for below fold, subtitles for mobile without sound.
03Alternative
A short motion-loop or a high-quality photo composition is often faster and no worse than a "talking head" for 4 minutes.