They do not read, like or repost for the ones they TAG (dusron ka padho mat par apna padwao)
They like and comment on one of your post only when they have posted something and want you to check it out (subtle)
They continuously like your posts (only like) to draw your attention to them.
They follow you and once you follow back they unfollow (mission accomplished)
Now this one is funny. Some "on and off" account deactivators have a funny way of saying 'Hi ! I'm back for a while now'. They just like one of your post. Not that they check and like all your posts that you had posted while they were deactivated. So, not really a fan of your writing probably. You've intrigued them for some reason and so they gallivant to your account on reactivating. Also, maybe sometimes while doing window shopping at your account they end up buying a post and pay for it with a like. (I respect this. Really. I mean it. Atleast they have the courtesy to drop a like. Better than the plagiarists and people who copy your ideas and sell as their own without letting you know that they stealthily keep crawling into your account for thieving).
Lesson learnt -
Never to follow someone who has many followers but themselves are following less than 10
Take screenshots of your followers, so that you can track who has unfollowed you after you started following them.
(i.e. Only if you want to play the follow unfollow game. I don't do it myself. Honestly.
But, by educating novices with these tips, indirectly I'll have my revenge with the smartees.... Ha ha ha (devilish laughter )