People on the go tend to prefer compact portable models they can throw in a backpack or purse, while professionals need the larger models which allow for lens options, flash guns, etc. Ease of use. If you can't easily operate the camera, you won't use it, no matter how spectacular the specifications, image quality, or appearance might be. Most well-designed cameras are pretty intuitive after a demo or two. You definitely don t want to pick a model whose appearance alone is intimidating.
Some models are indeed more durable than others.
Be honest on this one. Be realistic about how you typically take care of such items. If the camera will wind up getting thrown in the glove box or fanny pack, pick something on the sturdier side. Any parts and pieces that appear delicate during the shopping experience tend to prove delicate when put to the test. Many people don't ever look at the manuals, but for some people, they are lifesavers.