My bestseller

A few weeks ago, when I just had two books up for sale on Amazon, I decided to look at my stats to determine which of my books was selling the best.  I suspected that it would be Across the Pond, as that is my favorite and what I considered my best writing up to that point.  To my complete surprise, Christmas in Hell is far and wide my bestselling book.  When I did my calculations, I had sold almost 3x more copies of Christmas than Across the Pond.  That trend continued this month. 
Admittedly, I am not talking record-breaking sales.  I still haven't quite made my money back from all the book cover designs I had to purchase pictures for.  Every little bit counts, though, and I am proud of the sales that I've gotten. 
I am not sure why Christmas in Hell is selling better than my other books (I have since put two more books up for sale, Second Chance and Nuptials for Sale).  I do know that of all the books I've self-published, Christmas in Hell is what I would consider to be my weakest.  I recently reformatted it, but I still feel like it's not representative of my best effort. 
So, what is attracting people to this book? 
It has to be the title.  Everyone can relate to the nightmare that is the holiday season.  The concept of being miserable at Christmas must be something that most people want to read about.  Perhaps it is the idea of not being the only one who thinks it's awful to spend time with family (or worse, someone else's family!) at Christmas time.  Whatever it is that is attracting people to the book, I'm happy they found it and I hope they liked it.  I also hope that they give me a second chance and try one of my other books.  I'm excited to see how the book sales might increase as the holiday season approaches. 
I'm surprised, but pleased, with my "bestseller" and hope that it continues to do well (and maybe bring some of my others along with it).