Because sometimes even good Apple Watch apps get silly.
You can kill any Apple Watch app at any time by force quitting it. Though the implementation differs slightly, the idea is the same as the iPhone or iPad. More importantly, it's every bit as simple and easy to do.
Update: watchOS 3, because of the new SOS feature, moves force quit from double side button, to side button then digital crown. New steps below!
How to kill Apple Watch apps
Note: You have to be in the app you want to force quit before starting.
- Press and hold down the side button until the shut down screen appears.
- Press the digital crown to force quit the active app.
If force quitting apps didn't alleviate the problem, you can always reboot your Apple Watch. Historically, that's scared a lot of software straight.