Comment by MyOutfitIsVague

Mostly just zombies and signal handlers.

And your software can do it, if it's written with the assumption that it will be pid1, but most non-init software isn't. And rather than write your software to do so, it's easier to just reach for something like tini that does it already with very little overhead.

I'd recommend reading the tini readme[0] and its linked discussion for full detail.

[0]: https://github.com/krallin/tini