re; Poor finish, gummy materials, or sticking tools...applies to lathes, mills, drills, grinders
All comments on machine tool alignment of gibs and respective flats, properly clamped material [rigidity], properly mounted tool, tool orientation/ centerline, speeds & feeds, cutting fluids, are valid.
The physics don't work independently, though one or a combination will overtake others, or when all can be 'incorrect'. A better term might be unbalanced.
The single most common issue, I rarely see addressed; is the form of the cutting edges. There is little evidence the small shops are equipped to sharpen cutters; not only grinders/ wheels and honing stones but understanding regarding formation of proper cutting edges.
The situation is not entirely their fault. The marketing of cutters is not centered on HSS, the focus is carbide inserts and then cemented bits. A result of this, the discretion and motivation to learn grinding is no longer widespread; mislead that carbide is the universal choice.
If a gummy material is being worked then tools need a proportional increase in sharpness. Carbide does not 'cut' in the traditional sense. It uses hardness to plow or push material off, compared to HSS which shears. Soft material piles up instead of being carried away from cut zone. That generates heat, enough to 'weld' to a cutter. And that interferes with cutting. Which worsens chip ejection. Cutting fluids reduce that, softer materials are kind of a cut and try situation in home shop environments.
I'm away from home on a renovation project; since January. So my log-in rate has dropped sharply. But make your posts and message me through the site if there are questions, solutions or ...