Although I basically agree with most of what you write (which can be exemplified by the well known "garbage in - garbage out"), I don't think it is fair towards Jamal to suggest he isn't doing his best to get this right.
I didn't mean to suggest that Jamal wasn't trying; instead I was suggesting that
no amount of effort can make some data right, and that under certain conditions
trying harder wouldn't necessarily improve the situation. "Repair" is all well and
good, but it can't anticipate every data condition. Some data is intrinsically
incapable of correction; when you encounter some you need to be ready to
know when to give up.