What common mistakes do you see most often with Success Plans?

We're going into a session where we will be talking to a number of CS Leaders and CSMs about Success Plans. 

I'm curious from this group - what are some of the common mistakes you run across when implementing success plans?  Both from a leader perspective and from a CSM perspective.

@Alex Farmer @Sara Bochino @Matt Myszkowski @Kristi Faltorusso @Alex Tran @Will Pagden @Sheryl Hawk @Willow Moellering