10 seconds is fantastic, I'd love such a short processing lag
- Speed of light is not that fast.. really
- your computer has lag time doing real-time encoding (OBS stats window tells you what that is)
- then lag to send to stream host
- then most providers re-encode the video and then distribution as
@FerretBomb mentions
a little detail on that re-encoding? H.264 has lower processing requirements, so is a common PC to stream host format. [H.265 being a licensing mess, and AV1 having processing demands beyond even upper PCs]. But H.264 is inefficient in bandwidth, and for large stream hosts that is a show-stopper, so re-encoded... takes time [and possibly re-encoded to multiple formats], then distribution to CDN [more time]. Stream delay on Facebook can vary by watching device, even on same network. Try an iOS, Android, and PC on same network to watch same stream and note delay differences. Then watch over cellular network... entirely possible delay will vary (possibly by a lot) between devices