I've seen small twitter artists who had one tweet get really popular, with thousands of likes, and while their follower count might increase it's probably not a huge gain, and their engagement afterwards is only a little higher - eg. ~50-60 likes instead of 20.
It's a sadly common occurrence.
Something that might work (no guarantee) is what @Caro and @pilot-obvious said, try to post content that people will have a good reason to care about. From my observations, it's mostly currently popular memes, relatable comics, shipping and porn... Well, mostly, not exclusively lol. Also things with a very noticeable aesthetic that appeals to many people.
A work might be technically fine but few people will engage with it if there's nothing interesting about it. (ah yes, the bane of my artistic existence...)
Of course this might make you feel like a sellout, just pandering to the crowd, and could make you lose the drive to create but that's just the price 
...Take it from someone who's consistently failing at all of the above and losing 2 followers for every 1 I do gain once in a blue moon 