Decreasing Potential Payout.

I'm still very new to the platform and trying to learn how all of this works so please excuse my ignorance.

I've noticed that my last two posts have been decreasing in potential payout several times a day and I'm curious as to why?

Are my posts being down voted or flagged? Should I receive a notification if this is happening?

I would just like to have a better understanding of how it works. I appreciate your assistance.