The most beautiful day can turn miserable quickly. Being soaked to the skin is a rotten way to end a hike. This is one of my biggest gripes in the park. When you enter the park, pull ahead and park your car if you want to talk to the ranger. Stay on the trail, even if a straight line is much shorter than the switchbacks.
Short cuts cause erosion.
Damage to the tundra can take hundreds of years to repair. Back in 1980, we were returning from Flattop Mtn, when we saw a busload of teenagers tramping accross the tundra, totally ignoring the trail. I tried talking to them, but they kept right on going. Take nothing but pictures, leave nothing but footprints. And make sure your footprints are on the trail.