Internet Banking Security

I had "lost" my TANs and Phone Banking PIN - well, "lost" is not the right word, my children had acted as a shredder.

I do not use Phone Banking at all, so I called in asking for a new TAN list only. I was told that they would not mail me a TAN list, because they could not identify me without a Phone PIN.

So I inquired how to get a Phone PIN, which is easy enough: they can mail it to me!

So now I wonder, why mailing a PIN is so much more secure than mailing TANs? Any clues?

Anyway, with banks you have to play by their rules and so I did: I got the Phone PIN, rang them again, now having "proper" identification, asked for a TAN list, got it mailed, rang them again to activate it, and finally I can use Internet Banking again, the only downer being the phone charges I had incurred.