Is the cover of an ebook important when it comes to sales?

I've read where authors say it is important. From my own limited experience, I don't know.

At present I have 3 ebooks published. Two of which have covers I have somebody to make for me. I think they're good covers compared to the generic one from Amazon I'm using for the other book. BTW, I'm going to get another cover done for Coming Home.

However of my three books, Coming Home is the one I'm selling the most of. By a big margin too. My next book, Best Laid Plans, will feature a paid cover also. A raunchy cover for a raunchy book. It will be interesting to see if BLP breaks the losing streak I have with paid covers.