It was used as a threashold for posting on some communities, but mostly people are addicted to seeing the validation number go up and be higher than the one you disagree with.
On reddit, it's on your profile. You have a post karma and a comment karma. Lemmy doesn't keep track of that, it only counts votes per post and doesn't tally up the total per user.
I may be wrong, or it may be the app that's doing the counting. Either way, I guess it amounts to the same thing, you can definitely find the number somewhere. I know I can't check from a browser.