Notifications on your iOS lock screen disappear after you unlock your phone.
But you can recall notifications by pulling up on the lock screen.
You could take this a step further by using this feature as a way to configure unobtrusive notifications.
In Settings > Notifications, you can set a particular app’s notifications to appear only in Notification Center (and not on Lock Screen or as a Banner).
When you do this, you won’t be bothered by notifications on your lock screen unless you intentionally pull up as a quick way to check Notification Center.