So, I used to really like Barnes & Noble and spent many an afternoon there eating cookies and reading. I even got a membership there for a few years. As I got older, however, I found that the convenience of online shopping meant I went to bookstores less. It also didn't help that I no longer lived anywhere close to a big box store during my college years (or rather I didn't have the transportation to get me to one).
At any rate, most of my online business goes to Amazon because it has a huge selection of things which I can get with free 2-day shipping (yes, I have Prime) for not that much money. Also, their site is easy to navigate, and has a lot of nice functionality like the wishlist feature.
Recently, I bought the Groupon for Barnes & Noble and wanted to use it on BN.com because the nearest Barnes & Noble to me is still really far away. I found that the prices were competitive with Amazon (the prices didn't use to be competitive) which was a pleasant surprise. Because I no longer have membership though, I have to pay for shipping which, ok is not a problem because I could get membership.
Quite frankly though, I won't renew my membership because I can't stand the BN.com site. I established an account on BN.com sometime ago and wanted to update my password, but apparently this meant that I ALSO had to change my email or it wouldn't let me actually change my password. Seriously, I only want to change my password, don't make me change my email.
Second problem, during checkout I clicked on one of the help links, and it popped up a little message overlay which I couldn't get rid of to go back to editing my order, granted this may have to do with my browser (Chrome which has enough market share to warrant making things work properly), but if I have to start my checkout ALL OVER AGAIN, I'm much less likely to actually checkout.
Third problem, Amazon has this nice feature where I don't have to re-enter my giftcard (the Groupon was set up to be used like a gift card) information every time I check out. BN.com doesn't have this, so when I got booted out of the checkout screen because this damned help box wouldn't close, I had to re-enter all that information again. Yes, this is a small annoyance, but small annoyances make me not want to use the site. Not using the site means I'm not going to buy from the site unless I HAVE TO.
Basically, I'm trying to say that online shopping is about convenience. If an online store makes it inconvenient to check out or do anything with my account, it's less likely that customers will stick around to put up with it when there are store which don't have those hassles.