What's the deal with lowering the lifeboats on oars?

In the movie, they lower lifeboats from a higher deck towards a lower deck. They do that by letting it slide on oars. Yet it seems a very steep slope, making it look like a bad idea, even if there weren't so much panic. So was that historically correct? If so, would it even work? What the idea? Or is that just something in the movie, depicting people improvising? If so, hownwould these lifeboats on higher decks be used then?