It is engineered to be unpleasant to wake people up quickly and force them to interact with the device.
While "Radar" was the longtime default, newer iOS versions (iOS 17+) have introduced "Radial" as a slightly gentler alternative. Why The iPhone's Alarm Is So Annoying iphone_morning_alarm_sound_effect_annoying_ios_...
You can listen to the iPhone Morning Alarm Sound Effect (Annoying) on Asalh Love's SoundCloud. It is engineered to be unpleasant to wake