The main difference is that most people that use other software use the software to produce the desired results. The vast majority of Poser users use the software to assemble bought textures, props etc. As an example Poser users buy poses when the software they are using is designed to do just that. Poser has become, for a lot of people, just a grown up software version of Barbie rather than being used to it's full capabilities. Nobody is asking Poser users to build their own figures because Poser is not designed to do that but you can make quite complex props, pose your figures, do your own lighting and certainly develop your own characters. Most Poser users use a image app for postwork so again make your own textures.