One of the main draws of Amazon for me is that I can buy a piece of hardware, try to install it on my house/bike/project/whatever, and if it's physically incomp

One of the main draws of Amazon for me is that I can buy a piece of hardware, try to install it on my house/bike/project/whatever, and if it's physically incompatible in some unpredictable way I can return it. This enables certain things that are just not possible with the selection available in local stores. I realize this probably does not account for a large portion of Amazon returns though.