Comment by infamia

Because the words temporary amd nonimmigrant don't carry the meaning that you're imbuing into them. Fiance visas operate very similarly to these dual intent H1 visas. You're granted a temporary nonimmigrant status while you pursue a permanent one. The words nonimmigrant and temporary doesn't exclude pursuing a permanent status at all.

In the case of a K-1, it is assumed you will transition from a temporary nonimmigrant status to a permanent status. [1] Requiring folks to move to the U.S., and then go back out of the country to get a green card, only to return again, is absurd. That absurd dance for both K1 and H1 w/dual intents is the reason the laws and guidance provided to agents changed starting in the 50's through the 90's. These changes in guidance to agents are nothing more than a thinly veiled attempt to suppress people coming to the U.S. lawfully, which is absurd and deeply anti-American.

[1] https://www.uscis.gov/family/family-of-us-citizens/visas-for...