Ours sites are community driven. What is helpful to the site is important than what the user thinks. Author's intent is important but there's a reason we have community editing and moderation - to make posts better.
In such cases, the Community decides which is the useful edit or the right edit. Right and wrong is not subjective while following Stack Exchange guidelines. In the name of intent, a user can't edit wrong tags or wrong edits. There are clear guidelines from the help center. It is users who have wrong understanding.
Edits are expected to be substantial and to leave the post better than you found it. Common reasons for edits include:
To fix grammar and spelling mistakes
To clarify the meaning of the post (without changing that meaning)
To include additional information only found in comments, so all of the information relevant to the post is contained in one place
To correct minor mistakes or add updates as the post ages
To add related resources or hyperlinks
In the same article, there is a paragraph giving importance to the decision of community.
Editing is important for keeping questions and answers clear, relevant, and up-to-date. If you are not comfortable with the idea of your contributions being collaboratively edited by other trusted users, this may not be the site for you.
So, you should take some time to study the merits of edit. If you are just abusing your edit powers and rolling back for the sake of ego, then you are doing it wrong.
If an editor adds wrong tags which are corrected by another editor or if they are adding back some objectionable content, the community should respond. If you ask what is right and what is wrong, I will say, the experience and understanding site's policies better comes into the picture here. I believe there are users and moderators who know basic guidelines on how editing works and not take decisions favouring bad edits. So, there would be no problem in that. The problem arises when no one are acting and users starts taking sides.
The edit which provides substantial edit irrespective who is the editor will be restored. See Who has the final authority in an edit war? OP or a moderator?
Clicking rollback till the mouse buttons explode is a waste of time because there will be a flag to the moderators about edit wars if it done continuously. If you are not still satisfied, raise a flag for moderator intervention. A moderator should intervene if there is nothing solved between editors. They may lock it for some time. Such cases happened on our site too.
If there is no action from moderator for days, it is better to click Contact Us than flagging the post or clicking rollback again and again.