About Luck Quality Upgrade

I see anyone talkin here, at forum, about something like up the quality of a item lvl 15 with lucky time, if it durability get 0 and u let repair that, this have a chance to upgrade the quality, ok, here comes my questions.

1 - This is true ?

If this is really true:
2- What is the chances of that happen ?
3- Can i loose my equip
4- It will happen for all qualitys with same chances, of after any repair it can be dangerous.....

I think to, if this is true, why all the peoples dont collect noob weapons 2 socks and let try to get elite or super using it ?

Waiting a answer, thank you very much..........

if you have lucky time there is a SMALL chance of the quality being upgraded and it doesnt have to be 0 durability it can be anything as long as it repairs.

the reason people dont do this as a way to make money is because the odds are too small it would take a month to make something from normal to super just by upgrading

dont go expecting this to happen if it happens great if it doesnt move on dont become obsessive about it