Why does voice recognition increasingly recognize less names on my galaxy S8 phone with each update?

[Android Central Question]

With each update, "ok google" rexognizes less names. It literally mispells the same names it used to spell correctly. Even when I pronounce the name the same way it does, it spells it differently and says it doesn't recognize the name. It actually worked almost perfectly when it was first introduced. It's as if the voice recognition is targeted at a specific subgroup of voice and name profiles.