I bought my Nikon D40 from a camera shop. I spent a fair amount of time talking to the expert behind the counter, discussing what I would get if I were to buy a more expensive camera.
The expert was telling me how a more expensive camera might have more megapixels, it will be more sturdily built (hence able to withstand harsher conditions), and it will have more buttons on the body which would allow me to change settings quickly (instead of having to navigate through piles of menus).
I nodded, and let him know that none of this was particularly compelling. I gave him one last chance to upsell me. I told him that I had no intention of buying another DSLR in the next few years, so I needed to get the right one first time. Was the Nikon D40 missing any features which, in six months time, I would really really want.
No, said the expert. Definitely not.
Six months later, with an interest in experimenting with HDR photography, I discovered that the Nikon D40 does not have Automatic Exposure Bracketing. Fuck you, expert.