Smaller Diameter Wheels - What's the advantage?

[LLogan]

This year, I saw many veteran teams using wheels with smaller diameters than what I'm used to seeing and what my team has used in the past. I've seen lots of 4 inch wheels and some 5 inch wheels, as compared to the 6 inch wheels that my team uses and some of the KOP and Plaction 8 inch wheels that I've seen lots of rookie teams use.

What are the advantages of using these smaller diameter wheels? Of course, you can change the speed/torque ratios through chaining and gearing, so I don't think that's the issue. There is an obvious weight difference too, but I'm not sure if the weight loss is justifiable. The only other thing I can think of is the decreased amounts of rotational moments of inertia (smaller radius, less mass), leading to less strain on the motors when the robot accelerates or decelerates. Though, I am unsure if these are reasons at all for a team to choose smaller diameter wheels.

Are there any reasons as to why smaller wheels are advantageous over larger diameter wheels? If your team uses them, or if you know any good reasons, please share some insight.

Thanks!
-Logan