Board Thread:Episode Discussion/@comment-34633327-20180105193053/@comment-27648673-20180107014413

Azariahrobinson wrote: okay, so this is something I don't get about Juan's semblance, a semblance existence pretty much there to help the person that owns it and only that person the main reason for the semblance is to directly help the person survive. Semblances do not have to be helpful to the user (but usually, the user can find a personal application of it). They are simply a custom ability based on that user's personality or driving characteristics. In this case, a supportive and emotionally attached person got a support semblance.

You could say it helps him because it heals his friends, sparing him from emotional trauma and helping him fight in battle. Generally, though, Jaune's pretty selfless to the point where it's self-destructive or sacrificial, so his semblance (so far) has no focus on himself at all.