There is something about almost all of them that can be "tricky" if people aren't paying attention:
  • Hero On The Halfshell - we aren't supposed to kill the turtle?
  • Pulling Poison Posies - why do I keep losing health while standing in the poison?
  • All's Well That Ends In The Well - adds? Are we supposed to kill those? What do you mean the healer keeps getting silenced?
  • More Than A Feeler - there were bubbles?
  • Stinging Back - there are enemies that can heal?
  • Long Live The Queen - was I supposed to avoid the bomb explosion?

I've done all the guildhests many times while leveling all the classes and I don't think there is a single one where I haven't seen facepalm moments.