Hello ct9arlos2
It's because your item started the evolution with 8 base playstyles, and the cap is 9. Because playstyle upgrades are only given in the order they are displayed in the evolution tab, once a cap is reached on a certain level, those remaining upgrades are bypassed and you move on to the next level.
In your case, on level 1 your player already had 8 playstyles (including trickster base), so he only received quick step base (which makes 9 base playstyles). So on level 2, because low driven shot is displayed before quick step+, and as I said they are only given in the order they are displayed, at the time where the low driven base would have been given, your player already had 9 base playstyles and was therefore ineligible to receive it. Although the next upgrade converted quick step from base to plus, making 8 base playstyles, the evolution only goes forward and does not give previously bypassed upgrades. I wish it was more clear, and that those other sites you may have used would properly reflect how the system works, but I hope that my explanation has helped you. All the best to you!