You can check the quality of your sleep, as Vector automatically detects when you are sleeping and provides statistics in this sense.
Vector also automatically detects when you wake up, based on your arm movement. The watch detects your sleeping movements if the auto sleep detection is turned on in the Contextual Menu from the Settings in the Vector Watch app on your phone and if you wear it during sleep.
Sleep charts can be checked in the Vector Watch app and they provide information aggregated by weeks, months and years. You can thus check your progress over time. Just rotate the screen in the activity tab of the app to see the charts.
When the watch detects that you are wearing it while sleeping,
All alerts will be blocked, except for the silent alarms, while sleeping if you are wearing your watch. When you get up in the morning and take a few steps, Vector Watch greets you with a Morning Watchface that includes the weather forecast for the day and your first meetings.
You may find more details about the Morning Face in this related article.
If, however, you leave your watch on the nightstand, it will not track your sleep, but it will not disturb you, as it does not vibrate when left on the nightstand.