"You have to keep taking minoxidil forever"...? Even with finasteride?

I keep hearing people say this, and I wanted to ask about it because to my mind it doesn't make any sense unless you're using minoxidil as a monotherapy - seeing as it helps to put new hair on your head to replace what you've lost, my assumption would be that once the hair is there on your head again, it would be subject to the same forces of hair loss that affect all your hair in general, and won't be "special minoxidil hair" that will disappear as soon as you stop taking minoxidil.

Personally, I've just started experiencing androgenic MPB and have been lucky to catch it in the very early stages, and my doctor has said that basically going on finasteride will pretty much stop that process in its tracks or slow it down so much as to not matter...and then that minoxidil can be used to try and regrow what little hair has been lost so far.

In my mind, if I'm taking the finasteride, that ought to stop me from losing any of the hair hopefully gained via minoxidil use as well, even if I stop taking the minoxidil? But I keep hearing people say "once you start using minoxidil you have to stay on it forever or the gains will disappear" and I want to know why they're saying that? Do they just mean in the absence of a DHT-blocker like finasteride? Or is there really some non-androgenic mechanism by which minoxidil-gained hair requires the constant presence of minoxidil to be maintained?