Well, as psychological studies have shown, if there is groupthink around a specific issue, having one person be seen to visibly disagree with the group can make it easier for other people to disagree, which improves the whole group’s decision making process.
If you actually think that politician X is doing a decent job, and you are willing to say so in an environment where others may disagree with you, then that frees other people to think and act in a more independent way, improving the whole group’s ability to make rational decisions about politics.
Well, as psychological studies have shown, if there is groupthink around a specific issue, having one person be seen to visibly disagree with the group can make it easier for other people to disagree, which improves the whole group’s decision making process.
If you actually think that politician X is doing a decent job, and you are willing to say so in an environment where others may disagree with you, then that frees other people to think and act in a more independent way, improving the whole group’s ability to make rational decisions about politics.