If the trend in the burndown chart in fluctuating like Up, Stagnant, Down and 0 at the end of sprint. What does this indicate?

Scenario - 

Here I am referring to one particular sprint. Right from the beginning till the End of the sprint, I can see these patterns.

But good thing is it comes to zero at the end of the sprint. But coming back to the pattern question, what does it indicates, is there anything that can be done to avoid getting these patterns?