German here, this is the right definition, trying to improve something but ending up making it worse.

I still agree with parent’s definition more because it also covers the ironic, sarcastic case, as well as the inherent ambiguity of the word ‘besser’. Plainly put, ‘better’ for who?

If you just say it as a logical series of making it worse while making it better you miss that the intention of the ‘better’ is the first place wasn’t even the intention to make it better for the user.

Yes, that's the correct definition.

But you rarely only worsen it in every direction.

that's not disagreeing at all (american partial german, partial pole)

It is a different meaning from that in the parent comment by OroPla.