It should be added that new coins generated by mining require a full 100 confirmations before they can be spent.
100 confirmations exclusively for miners? This is something new for me. I don't understand why there is such a difference between mined and transacted coins.
It is to be 100% certain that the new coins are and will remain valid. Because they are buried so deep before they can be spent they are in theory 100% safe from all foreseeable chain reorganizations.
Same 100% safety of course applies to normal tx's as well but most folks/businesses feel comfortable with 3-6 confs because reorgs due to orphan races stretching deeper is extremely rare: As I recall, possibly only happened once a very long time ago?