This is a weak hashtag.
First, it is boring and not unique to the team in any way. Literally every team could have used this. Should have just gone with #GoJazz, at least it is short and anyone seeing it would know what you are talking about. Other boring, yet still better, options include: #JazzBasketball, #JazzBall, #JazzNation, #UTJazz. More clever things would relate to the state and/or the life cycle of the team: #NextStep, #AlwaysUp, #JazzFight, #Crescendo, #Elevating, #RiseToChallege (these are just off the top of my head).
Second, it is a clearly false statement. The success of this year is not just based on the team performance. Individual player development also matters and in some cases could be more important than the team performance (i.e., I would rather see Mitchell become MVP and loose in first round than have him digress and Jazz advance to second round).
Anyways... that is my 2 cents.