Like ThirteenBox, the only reason why I would put off the last episode(s) is because I don't want the drama - and the pleasure - to end.
Some endings aren't what I was expecting, but all in all they rarely change my opinion of the drama as a whole. I agree with you that Down to Love didn't have a spectacular ending, but then no Taiwanes drama I've watched so far had one, really.
So, unless they are so random and ludicrous that in the space of a couple of episodes they manage to ruin everything that was - perfect example Love Keeps Going - I don't really mind the ending so much. On the other hand, a very good ending can make a good drama into a brilliant one.
I digressed, sorry.
To answer your question: no, I don't put them off. I have put off a drama by the middle though, and it was a huge mistake: on picking it up again, the thrill was gone.