Is there a reason Ten didn’t debut with 127?

I’ve been listening to NCT since 2018 but I only started to fully stan them since 2022. Can someone explain why Ten was never put into 127? He’s included in a lot of group activities (i.e Taeyong/Jaehyun enlistment send off) more than a lot of other members from different subunits. Is there lore behind this decision? Wayv is my ult unit but I have always been surprised that Ten didn’t debut much earlier in a fixed unit.