It often doesn't take much to put a new customer off ebooks. The first few purchases are crucial for forming their impressions of the format, the product and the publisher. I pay close attention to what readers are saying online about early ebook buying experiences. Whether they could get the book, if they couldn't get the book whether they could contact customer support.
And when they got the book whether it met their expectations.
One recent comment I read, which seemed more than fair was this--readers tend to assume a work is a novel. If it turns out to be a short story they can be a little dissappointed. It seems to me that at some epublishers the length labelling could be a little clearer to avoid this kind of unpleasant surprise. Word count, page count, and if some in house terms are use they should be a clickable link to defintions and misleading. Novel should mean novel? Something that if bound in print would be book length?