Because I could smell me from here!
Seriously though, recognizing I was addicted to cigarettes and recognizing vaping was a healthier alternative to getting the nicotine I so foolishly let myself get hooked to it was a no brainer. Besides, my Significant Other, (who has never complained about my smoking), suggested in a passingly casual kinda way that it would be nice to have an extra decade or two together that smoking might not let happen. Also, there was the whole health thing, cost savings, smell, taste, the fact I didn't have to go outside to get my fix, etc., etc., etc..
And about that smell thing,, now when I take a shower (yes it's daily and sometimes twice or more!) I actually smell like I took a shower, not like I bathed in smoke... It's nice to smell pretty or at least clean for more than an hour!