Just some uninformed speculation, but - looks like he put down something like painting tape where he wanted the raindrop trails, painted a light coat over the whole thing, removed the tape, and then painted the drops. Feel free to correct me.
Personally, I think it's meant to be a deceptively simple painting. At first blush, it doesn't look like much, but then you notice the streaks and then the drops and it pulls you in.
I'm sorry if you misunderstood me, friend, but if you'll kindly point out where in my comments above did this "taking it personally" occur, I believe I might better understand.
FYI, "To each their own" is not a derogatory phrase, and if that's where your irritation lies... the irony in that alone is tragic.