Sometimes zig-zag fluctuating chart turns out to be a BFP and picture perfect charts is a BFN. The good news is, if you have a bad chart, don't worry too much about it. It could still turn out to be BFP.

As for the good charts, at least they can tell that their body is working like it is supposed to.
I'm addicted to charting, every morning I wake up, I wanna know what my temp is.