Docker has been reliable enough on my home server that I never thought much about the latest tag in my Compose file. That changed the day I decided to test Jellyfin’s release candidate version 12 before it went stable. Weeks later, my container refused to fetch the finished build. Chasing that down sent me into troubleshooting mode, and that’s when I learned what the latest tag really is, and what I a**umed about it turned out to be wrong. The latest tag isn’t a promise about version numbers; it’s a tag that someone else controls. Understanding that changed how I write every image in my server’s Compose file.