OBS is what everyone reaches for first, and for a show with you at the desk it is the right tool. For a channel that has to stay live for days, it is the wrong one, and not because of anything OBS does badly. The problem is the computer it runs on.
OBS encodes the video live, on your processor, and sends it out over your connection, for as long as the program is open. That means a machine that never sleeps, never updates, never loses wifi and is never needed for anything else, running at a good fraction of its capacity, indefinitely. Home computers are not built for that, and home connections are not either.
People try a spare laptop, then a mini PC, then a virtual machine in the cloud with OBS installed. Each step costs more and each still needs someone to look after it.
A service whose only job is to send video to platforms from its own servers. You upload the video once, the service prepares it for streaming, and from then on a start is a button rather than a program. No encoder on your side, nothing to install, and the stream does not know whether your computer is on.
That is Beamd. It is not a replacement for OBS in general: it does not take a camera, a screen or a microphone. It takes files you already have and keeps them on air.
The usual reason to keep OBS is a title bar. Beamd can print a fixed line or the name of the playing video over the picture, set per stream, so a now-playing caption does not need an encoder on your desk.
A live show with you in it, a game with commentary, a camera at an event: keep OBS. Many channels use both, OBS for the live hours and Beamd for the twenty that follow. The stream key is the same either way, so the channel does not change.
Stream 24/7 with your computer off