Writing for iDownloadBlog, Jeff Benjamin notes:
"Unlike the iPhone, if someone steals your Apple Watch, they can easily reset the device (bypass the passcode), and pair it with a new iPhone logged in to a different iCloud account. In other words, it’s totally feasible to steal an Apple Watch and set it up on a different device as if you just purchased it from an Apple Store."
Jeff later goes on to note, "It's not a security problem from a user data standpoint, but it is a security issue from a device theft standpoint," and that's certainly true. Your data lives on your iPhone, so pairing an Apple Watch to another iPhone or iCloud account won't put your data in jeopardy. That's cold comfort when your Watch is gone, though. I wonder if Apple will institute an activation lock for Apple Watch in the future.
In the meantime, add a passcode to your Apple Watch.
This posts goes out to Ken Snider, whose name I regrettably left out of our Patreon thank-you earlier this week. Sorry, Ken!