'persistant' label was counter-intuative (to me)

[] Persistent captchas
If checked, the user will always have to solve a captcha. If not checked, the captcha check for a form will be omitted during the rest of the session once the user has successfully solved a captcha for that form.

Addmittedly it was my own speed-reading at fault there, but I got the idea
- User only has to do the captcha once, sounds cool.
... enable that feature, yeah.
Tick box.
... test. test. decide it was not working with previews ... etc. Applied preview patched release.
Still not, check settings again ... finally actually read the words, not just the title :-}

"Persistant" to me meant the result hung around and didn't have to be done again ... not that new challenges kept arriving each page. Just a language thing I guess.

Wording like "New Captcha Challenge on every form" (the current behaviour)
vs "Don't ask the same user again" (What I thought the checkbox was indicating) would have stopped my small period of confusion.

I know I won't forget again in a hurry, but perhaps the title could be clearer.

_{Again, yeh, the answer was staring me in the face... My fault, I know}