Normally we can say that [...]
One confirmation: a secure transaction, but reorganizations and double-spending can occur.
Then again:
Is there anyone who has ever lost Bitcoins to a double spend attack after 1 confirmation? Personally, I have never come across such a case.
Have you come across such situation, Yamane_Keto?

Yet since you insist of the magic of number 2, I can not say anything else than what was given until now as argument. Perhaps UniJoin may explain you more clearly which they chose 2 confirmations.