Is this because you're essentially picking two doors? One of the ones you pick will always be wrong because there is only one correct door, but one will potentially be right. Just because the host picks an incorrect door and you pick the potentially correct door doesn't change the odds, you're still picking two doors out of three.
So when you make the first choice the chances are 1 in 3, then they rise to 2 in 3 once the host has already shown you an incorrect door?
Is this because you're essentially picking two doors? One of the ones you pick will always be wrong because there is only one correct door, but one will potentially be right. Just because the host picks an incorrect door and you pick the potentially correct door doesn't change the odds, you're still picking two doors out of three.
So when you make the first choice the chances are 1 in 3, then they rise to 2 in 3 once the host has already shown you an incorrect door?