Would you mind if I create a strawman of an edge case to test your devotion to the use of the word 'never'?
That is a fairly absolute word, and I tend to doubt you actually mean never.
That is a fairly absolute word, and I tend to doubt you actually mean never.
Alright say there is a pretty decent leader who has a personal trait which would make them unelectable to the public, but really shouldn't in any reasonable situation effect their ability to lead and make decisions. Is it in the public's best interest to know about that trait prior to the election?
Yes. Elected officials are representatives of the people. If that personal trait really does make the candidate unelectable, it means that the public does not want someone with that trait representing them. It's therefore in their best interests to not elect that person, since said person is not an accurate/desirable representation of the public.
> but really shouldn't in any reasonable situation effect their ability to lead and make decisions
Then why would it make them unelectable?
Because enough of the public is bigoted and fearful of personal differences that through out history many traits such as Polio, being Catholic, being single, being black, being a woman, being gay, and being a transsexual have been and some continue to be big enough deal breakers to enough people that a candidate will not get elected if they openly have that trait, regardless of how preferable they are to the public's best interests.
People are stupid, and honestly if hiding the fact you have polio is the only way you can get elected and help the country you live in, then damn it you should hide the fact you have polio for the time being. And later when you do reveal you have polio maybe people will become a bit more accepting, and realize how little that really mattered.
What I am saying is that your pure transparency model would be great for a theoretical democracy where equality and rational thought actually existed, but for the world we have, the democracy we have, transparency isn't always best.