Two paths exist, and confusing them wastes hours. The direct path is a tvg-logo attribute on each channel line in the playlist, which is a plain image URL the app fetches and draws. The indirect path is a picon set, where you point the app at a folder or archive of images and it pairs each file to a channel by tvg-id. Neither path uses the channel's display name, which is why renaming a channel to match a picon filename accomplishes nothing at all. If artwork is missing, the first question is which path your setup is on, because the fix differs completely between them.

Television apps are stricter about image requests than phones. Many refuse plain http images inside an https context, so a logo URL that renders fine in a browser on a laptop silently fails on the set. Some also cap image size or reject content types that are not what the extension promised. The test is quick: paste one failing logo URL into a browser and see whether it returns an image at all. If it does, and the phone shows it while the television does not, rewrite the URL to https where the host supports it. If the host offers no https, that logo will keep failing on strict apps regardless of anything you change locally.

Usually from the playlist itself, generated alongside the channel entries and pointing at images hosted by whoever built the file. That means artwork can change or disappear without any change on your side, and it explains why a full logo set can go blank after a routine playlist refresh. The alternative is supplying your own set, which some players support by mapping images to identifiers locally. That takes editing work and needs re-checking whenever identifiers change, so it is worth doing for a short curated list and rarely worth doing for tens of thousands of entries.

Not on their own. Artwork sits entirely outside the video path, so a channel with no logo can carry a clean 1080p stream at 5 to 8 Mbps while a channel with perfect artwork carries a stalling one. Judge a service on playback, bitrate and uptime instead. Missing logos do become informative in one pattern: if identifiers across the whole file are blank or nonsensical, guide data will also fail to match, and that suggests a playlist assembled carelessly. So read blank artwork as a hint to check the guide, not as a verdict on stream quality.

More than people expect on older hardware. Every visible row requests an image, so a list scrolling past thousands of entries can queue thousands of fetches, and a television with limited memory will stutter or hang while it works through them. This compounds the general list problem, where players destabilize past roughly 18,000 visible channels. Hiding unused groups reduces both loads at once, since artwork is only requested for what is drawn. If your set is slow with logos on and smooth with them off, that is not a fault to fix; it is a hardware limit telling you to trim the visible list.