It makes sense to assume "the more people know you, the better you will do on a new platform". I got 120 followers in a month, only thanks to my YT audience and not because what I write or post is popular on Steemit. Others I brought in, struggle to get a few followers since they have nothing to be noticed.
Everybody does better with promotion and advertisement. Whether it's shoutouts or resteems or tweets, the more others help you spread your content, the more popular you become. And for that you need a pre-existing fanbase or be veeeery patient while you slowly build one.
I was growing my fanbase for 5 years before joinning Steemit, and I still have only a fraction of them here. It's not much but it's a good early push.