The chain goes back until things no longer apply.. as others stated here, until time doesn't exist.
Time "emerged" due to something that happened. this means that something probably started this process as time has no will. (unless you think it does and that is a whole new OP
)
This is the Logic i used:
A rock is not a living being and has no "free will". if i see a broken rock,. i assume something broke it.
If i suspect this rock does have a "free will", i can assume that either it broke itself or something broke it.
I would be quite weird in my POV to say that maybe it just broke out of the blue without a cause.
If we establish its logic to think this about a rock... wouldn't you suggest its logic to think like that about a star? or a galaxy? or a universe?