Her main problem is she cannot stand on her own, she desperately requires a walking stick for her to continue down this path of resetting the loop, She did everything not for herself, but for madoka, She wants to see her safe so she gives up her life for it, she see herself as worthless, a piece of scrap to throw away for madokas happiness, and she wants to prove herself, that she can do something good after all, that she can save someone, that she can do it, She will save her. She will save the only good left in this god forsaken place.
When the reason for you to continue down the path of pain is not your own, It will be very easy for you to fall because that walking stick you hold Is someone else's property.
And when the person takes it away, they won't even look back upon your corpse, or those nail marks you made to get it back.
Tell me, doesn't that sound familiar?
For Netzach, his lesson is to live even when there's no reason for you to live.
Also I might have used wrong words, i mean she needs to have more self worth, to live not just because someone else but for herself, and a wind up toy can never be that because a toy needs a master, or it dies broken and unwanted like that old teddy bear.