For me, I intend to get down to 0 mg. nic. I started at 24mg, I am now down to 3mg. I mix my own from 36mg. Why? A lot of people might not like this answer, but because I am not a trusting person. I don't trust 100% that vaping is completely safe. I know nicotine is a poison and while there is no proof that nicotine is carcinogenic, there is equally no proof that it isn't. Do I think vaping is safer than analogs? You bet! Do I think it's harmless? I don't know. As others have mentioned, there are cardiovascular implications. So, harm free, I doubt it. Not trying to be a downer here, just being realistic. Much less harmful, yeah, I'll buy that. Just remember that if something seems too good to be true, it's usually because it is...
Beyond that, I want to get down to 0mg nic. because I don't want to be one of those people that I keep hearing about that are addicted to nicotine for the rest of my life. Addiction to me means you can't get enough of something. Be it nicotine, or drugs, or caffeine, or alcohol... Too much of anything, is not a good thing.
Anyway, that's just my opinion. Right, wrong, or indifferent. Thanks for taking the time to read it