Stuck in the middle of nowhere, in the afternoon without a winch. To far to walk back, not enough daylight anyway. Just an example how fast things turn for the worse.
Its no different with hiking. You can slip, break your ankle or stupidly take the wrong turn and get lost. Even weather can change an you have put yourself into a survival situation. Don't assume people will find you, don't assume the rescue helicopter can lift-off when you mange to press SOS on your Garmin. Maybe your batteries died or your Garmin died or you simple lost it somehow. Stupid things happen. Your
gear is your
lifeline and it can also make your life, your hike, your world a lot easier and enjoyable without ever having to worry.
In the military they say:
"Better have it with you and not need it, then not have it when you need it"