Something else to think about is the way different resistors and other components have been graded over the decades.

For instance there were manufacturing approaches where a target value was produced for a large number of components, but the manufacturing tolerance was a very wide +/- 20%.

The parts were then graded individually into the 1%, 5%, 10% and 20% bins, marked and priced accordingly.

If you then specified the lowest-cost 20% parts, none of them were actually any closer than 10% to their nominal value.