The revolution slider is a way to animate a web page based on a wordpress plugin. When you create a slider it start to be animated directly when the page is loaded. So if your slider is on top of the page it is perfect but if your animation is on the middle / bottom, the animate will be finished when the user will scroll to that part.
I just got an error message coming from wordpress saying on the index page that the connection to the database is not possible. I expected a problem in the connection chain but the real issue was related to a corrupted table in the database.
This as been fixed by repairing this table. So take care of the messages that can be wrong in the index page. The message in the admin index page was better concerning this point.