Again, this is not a rule. It’s just an observation about verbs with {-meH} in canon. A Purpose Clause, complete with subject and/or object can apply to a noun, and it’s possible that a maybe-infinitive verb-with-{-meH} could apply to a verb, but it is common for the maybe-infinitive construction to be applied to nouns, and less common to see it giving the purpose of a verb.

A canonical counterexample: qaSuchmeH 'eb opportunity for me to visit you. http://klingonska.org/canon/1998-01-18b-news.txt

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