I have good level items, but they aren’t different from 1st lvl. I’m in courage!
Well, if you want to craft a 4-star item, you need to have the 3-star item leveled up to 5, and with 5-star the same, but then with lvl 10.
Also, sometimes you get bonuses on gear, like damage bonus or charge time reduction.
If your talking about heat level, as your equipment levels it will get small increases to its stats. When you look at a level 1 item, the partially translucent part in blue is the amount of damage/whatever it will have at level 10. One top of that, at levels 5 and 10, many items will get bonuses.