I hear that a lot, but I familiarized myself with it once and ever since it makes a lot of sense to me.

Source ending in “/“: You want what’s inside. Source not ending in “/“: You want the thing (i.e. directory itself). For the destination, it does not matter whether it ends in “/“ or not, but for consistency I like adding a “/“ anyway (I want to put thing inside the directory).

It's a big source of confusion with cp. One of the UI reasons to use rsync (for mundane non-remote copying) is that it doesn't do different things based on what's present on the target.

> Was there already a /tmp/services directory on the dest?

No. And just to make sure, I ran a quick 'rm -rf /tmp/services' on the remote host, then re-ran openrsync on the client. Same result. This is OpenBSD 7.9 on both sides.

And I 100% agree about trailing slashes.