Am I understanding Resists correctly?

[DJSamhein]

Maybe this will help you understand it better:

@DJSamhein

What it means is that going from 0% to 1% resistance means 1% damage reduction. And going from 10% to 11% means a 1% damage reduction. And going from 74% to 75% means a 1% damage reduction. Likewise, increasing your maximum resistances from say 75% to 80% means a 5% damage reduction. And if you managed to reach 98% maximum resistance and increased it to 99%, it’s still 1% damage reduction.
So in LE, each % in resistance equals the same % in damage reduction for that type.

This is completely different from other games because resistance has a much heavier weight to defenses.
For example, in PoE going from 74% to 75% resistances is actually a 4% damage reduction. Likewise, going from 75% to 86% is a 78% increase in reduction.
And ultimately, if you had 98% resistance and increased it to 99% resistance, it would be a 50% damage reduction.

There’s also a few clarifications further down, but that is the basic principle of resistances in LE.