Well it's at least an indicator something has gone terribly wrong. Your project management software, one of the flagship features of which is reporting - now tells you essentially "no work is being done". Somebody in management panics, the team is told to get its act together and some variation of "improve the numbers". Yet features are getting shipped and clients are happy. The two most frequent (bad) options teams take to get out of this are:

1) Ignore the burndown chart / any other reports. Everything is fine on the business side, so let's just accept that the reports are broken and not spend time trying to fix them.

2) Have everyone invest more time into using the system (usually on an ongoing basis), so that it produces the correct looking down-and-to-the-right chart.

The problem is that with #1, the software is arguably not producing much value, if any. The problem with #2 is that you're spending extra energy and effort to make the software happy, even though outside of the software it seems like your team is working well, shipping features and keeping customers happy - all of which are more important than a pretty graph.