you also could have just "lucked out" and received a bad batch of coils.
I've gotten a whole box of bad ones before, well, where 4 are bad and only the 5th one works.
This happens. Does't mean the next batch will be bad. Dunno if anyone brought this up or not.
You may want to let the coil soak in the ejuice for 10-20 minutes if necessary.