Originally Posted by UBRocked
SigmunDroid...I don't think he's laughing at you...there is a back story here and some friendly disagreement about wiping partitions multiple times and whether or not it is actually better than wiping once. Haha!
Once, twice, three times a lady! ... Wiped
... You know, this is flash memory we're talking about. Theoretically, once a bit state has been changed to 0 or 1 it's permanent (minus the effects of extreme age without any applied power). This isn't like a HDD where heat can affect the stability of bit states (See superparamagnetic effect).
I suppose it all depends on the level of wiping it's doing. If it's only wiping the partition table, the data is still there; the OS just can't read it because it has no reference on how to convert the string of bits into something usable. If it's actually rewriting the partition with all 1's or 0's (essentially a full wipe) then there's no data there at all. In either case, you should only have to perform the wipe once. The only way you'd need to do it again would be if the utility performing the wipe is wholly inadequate and isn't doing its job.