When I started vaping I wanted to stop smoking but from day one my daily cigs declined from 25 to 5 and I thought, why not leave it at that. But then I thought, that's 80% control. May be 100% would be nice. I decided to leave the 5 cigs alone and learn to vape. 6 weeks later a combination of circumstances persuaded me to try for zero cigs and it worked.
So now I have 100% control. To prove it to myself I've smoked about 5 cigs in the lasst 20 months, also to prove the accomplishment to a few friends who still smoke. Those cigarettes tasted awful. I felt no temptation to have another. Quitting is not the same thing as control.
What I counsel is, if you vape you'll smoke less. If you don't stop vaping eventually you'll stop smoking.