We all heard it said that someone's respect has to be earned, that people need to show their sincerity to prove their character is worth respecting. I think that's largely incorrect and that everyone should be respected UNTIL they should that their character ISN'T sincere. What do you think, should respect have to be earned or should it be given with the benefit of the doubt?

Definitely given with the benefit of the doubt.

But I don't think the sentiment that it has to be earned is off base, if it is taken more literally. For instance if you and I are introduced and you treat me kind straight on from the first handshake, I am going to respect you with eye contact, interest in what you may have to say, and just generally, treating with respect. Because you have "earned" it by greeting me with respect.

Now, if you are introduced to me and you mumble a hello while your eyes scan the room, I am probably not going to put much into getting to know you.

Same for anything, a new teacher or boss, has "earned" the right to be respected due to their position of authority. And from the point of initial meeting, that "respect" is only theirs to lose, should they act in a disrespectful way at some time.

There's a difference between trust and respect. Trust has to be earned, respect should be given with the benefit of the doubt.