Or more specifically, why did I choose FreeBSD over an alternative like Linux? What follows answers that question. If you'd rather skip to specific examples, check out reasons I prefer FreeBSD.
For twenty years I relied solely on Linux my two home servers. One is my "do everything" server. Serves files, connects to IRC, monitors RSS feeds, tracks my TODO list, runs a restic server, GPU transcodes videos, etc. Essentially if I have a server need I use one system. The second server mostly just keeps a second copy of my data. The two stay synced with Syncthing and each takes regular snapshots of data. The second server also pushes backups to a third party so I have a complete 3-2-1 backup strategy. (And you should too!)
Stale Broken Packages Provide Motivation to Change
I had been happily using Void Linux for four years when suddenly LXD broke. Upstream LXD relied on a specific output from the Btrfs toolset. The Btrfs project changed this output as part of a major version update. Apparently the LXD project didn't account for it and as a result, LXD had a partial break when using Btrfs storage. Luckily my existing containers worked fine, but I was unable to create new containers. Not a big deal I thought. I don't create new containers so often. So I waited. And waited. And waited.
Three months later, the upstream LXD fix had been available for weeks but the Void package lagged. It's the unfortunate reality of smaller distributions. Staying up-to-date takes time and effort, and when I contacted the package manager he said he didn't have time anymore to keep things updated. So while I empathize with the Void project, it got me looking for an alternative.
I tried Arch for a month or so. While I love it on my laptop, the churn is a bit much on a server. As luck would have it, while trying it I had an LXD-like issue with QEMU during a major version change. The break wasn't quite as bad, but it was annoying and required manual intervention to reboot a VM. I decided I was done with rolling distributions and started looking for something more stable.
The Easy Search for Stability
While considering options I read a comment somewhere, "everyone's a Debian user, some just don't know it yet." Debian can feel a bit stale sometimes, but it is synonmous with stability. Moreover, it has a strong reputation for security too.
It seemed the obvious choice. I decided Debian would be my new server OS.
Curiosity Leads Me to FreeBSD, Experience Hooks Me
FreeBSD was never part of my plan. But I have two servers and they both had Void, which I wanted to replace. I figured it might be good to have two different OSes so if something breaks on one, hopefully the other doesn't suffer the same problem.
So I installed FreeBSD just to see. Like Debian, I was aware of its reputation for stability, but I somewhat expected I'd change my mind and flip back to Linux. But as toyed around and experimented, I kept thinking, "hmm, that's nice, I think I like this feature better than in Linux." After a few weeks, there were lots of these. And after a few months, I made a big decision: FreeBSD would become "do everything" server, and Debian would pickup the role of mostly backups. I captured many of the reasons I prefer FreeBSD in a series of short articles.