Learning about Transcoding/ Bitrate

[DeanoVIP]

Thank you for the answer, apologies further stupid questions:

HEVC 8bit and 10 bit - I assume one just offers a higher quality?

With Jellyfin determining if a transcode is needed, why does some of my H265 get transcoded and others don't, I would of assumed they were the same?

Is it worth converting 264's to 265's with Handbrake or am I just saving on disk space?