It stops when you are able to accept that what you have is good enough, this varies greatly from person to person..
Before I got the eGo kit, the standard 510 just didn't do it, and even though I "quit" analogs after 3 days, I still occasionally snuck one. I got caught and threatened by the wife with castration if she smelled smoke on me again, so I got the eGo-C and haven't needed a boost since. I kept trying, sometimes really frustrated with leaks or poor performance, but I stuck with it.
My current setup is an eGo 650mah passthrough with a Vision V2 non-rebuildable clearomizer. With Halo juice it gives me what I need and is far less hassle to maintain than the eGo-c. No leaks so far as long as I don't put it in my hip pocket. (they crack).
Keep trying different setups, it took me some time to find exactly what worked for me without mods, since I don't want to have to spend hours maintaining it. Now that I found the one, I will stick with it until the next great thing comes out.
Try new hardware and liquids out until you find what fits your individual style and needs is still cheaper than smoking analogs. Just do your homework before you buy instead of blindly buying the next new product every time.