I’d say getting millions of Youtube subscribers is one lucky hit. Just like in show business, there is that thing called x-factor which means it is an undefined reason why a an actor or celebrity becomes popular. With videos on YouTube, they are on the same vein that you need luck to have a trending video much more get many subscribers. I know of people who have uploaded so many good videos, funny, controversial, or even dramatic but they failed to get a thousand views nor a thousand subscribers. But I believe with perseverance so it is all right to push with your ambition and upload as many videos as you can.