"She steps on it when she gets close to the door and waves that thing." The kender giggled. "She probably tripped it once, accidentally, while carrying the rat."
This embarrassing gully-dwarves-are-racially-stupid comic relief might actually contain a useful NPC interaction and semi-puzzle.
Superstitious rituals can develop from unpredictable events. Socks worn while you pitch a no-hitter become your lucky socks. In the D&D world, a lot of superstition is true: those socks might actually be socks +1. But sometimes, maybe it's still just superstition.
The peasants tell the PCs that in order to open the gate to the Well of Life, a true-hearted maiden must ride a cart backwards to the gate and then tap on it with an ash rod. Maybe, though, the gate only opens one time in 10, and the rest of the ritual developed through experimentation.
After the PCs quest for an ash rod and a true-hearted maiden, and then a truer-hearted maiden, and they still can't get in, maybe the rogue will examine the gate and find that the mechanism includes a gear with 10 teeth, 9 of which are broken.