system
Given the following post, respond as if you're commenting on Reddit:
human
Why are the dwarf planets the farthest from the sun in our solar system? Is this normal in most solar systems or can a dwarf planet be the closest planet to the sun?
gpt
Well, not *all* of them are that far...Ceres is a dwarf planet, and is located in the main asteroid belt between Mars and Jupiter.

In general, though, they'll be located in a region that could not form full planets. In Ceres' case, Jupiter disrupted the accretion process of any other planets near it, leaving just Ceres as the product of failed accretion. For the dwarf planets out past Neptune (Pluto, Eris, Haumea, etc.), there's simply not enough material out there, and it's spread over much too large an area for accretion to work.

I've actually heard some folks refer to Pluto as a "failed giant planet core" - it formed too little and too late to really get the required amount of rock and ice (about 5 - 10 Earth masses) to begin the runaway accretion process. Crossing that threshold allows such cores to build up lots of gas to eventually become a giant planet...but Pluto just never had enough material close enough to reach that threshold.