That's not my issue. I didn't not open the topic because I am confused by the fiction. I opened the topic, because the rules seem to contradict.

It says, they reduce damage dice, but some of the devious monsters instead have a roll twice, take worse result. An effect that is not supported by the rules as written.

Conversely, I can't find any monster effect that gives a roll twice, take worse result.

Is that really necessary? Considering that a wizard will probably have a lower strength than a fight or paladin any way? I think the more straightforward the better.

For what it's worth, this is the general go-to list I use for Defy Danger weak hits:

Worse Outcome: You're out of the danger, but now in a new one.
Hard Bargain: You're out of the danger, but it costs you something, right now.
Ugly Choice: You're out of the danger, but now you have to make a choice with no particularly good options.

The key thing is that they do what they set out to do, but... Also, I've noticed that if the danger itself is not well defined and the fiction going on at the moment not detailed and engaging, weak hit results on DD will be harder to arrive at. In pinch like this, I'll turn it back on the players. Someone will have a good idea if I don't.

That is an immense help. Both the description about what worse outcome, hard bargain and ugly choice can mean, as well as the comment about weak fiction.

Both should be in the book in some form.

Maybe it would be good to have a chapter in the book about level 10 characters and what to do with them!

I second that!