Basic/fundamental topology question

what exactly, in words, is clean topology or a clean mesh? visual examples and “getting it” intuitively is one thing, but it feels like knowing what it is and what the aim is would make it faster and easier to achieve.

beyond that an optimized mesh is one that uses as little as possible to get as much as desired or possible right?

One possible definition:
“A 3D mesh with efficient polygon distribution, proper placement of polygonal edge-loops, few or no triangular faces (as opposed to 4-sided “quads”), and clean precise creases that minimize stretching and distortion.”

Though in that definition would you know exactly what is meant by ‘efficient polygon distribution’ or ‘proper placement of polygonal edge-loops’ without being shown actual examples.

In the case of organic models such as people and animals, clean topology also implies good edge flow, where the face loops follow the contours of the body in a way that will contribute to realistic deformations during animation. This description is contained within Richard’s definition, but it’s stated as a little bit more practical example.

this makes sense. how do poles relate? does a clean mesh use as few poles as possible or as many poles as needed to try to get the best possible deforms and edge flow with the fewest polygons? the latter can get kind of annoying when trying to select a loop and its redirected to multiple times to multiple different places.