Question about upgrading quality, help

If I upgrade my legend item to 25% quality, will it turn into mythic? Thanks ahead~

Nope . It just increase base dmg, and in return it will give more chance to get max cap affix

no it wouldn’t, quality increase the stats your item gives for equipment it increase AR for weapons it increase dmg, it also increase your chance for higher re rolls when using diamond or other crystals on your gear
if you want mythic you need to put 4 certain mythstone together in a specific order to turn it into mythic
look at legend codex or on forum for more info regarding this

Ex. If your wrap has +25% quality you can get 5000+ wd affix using topaz or fluorite