The cliff at the end
For several sprints, the MES team's burndown chart has stayed almost flat until the last two days, then dropped sharply. In daily meetings, most stories are “nearly done” for most of the sprint.
On the release level, stakeholders complain the team is “slowing down”, but the burn-up shows the completed line rising steadily while the scope line climbs even faster.
Both charts were telling the truth; nobody was reading them correctly.