Why ViewModel is still alive after I replaced fragment in Android?

Question

I use BottomNavigation in Android,But,After I replace RotationFragment to ScaleFragment,Back to BottomNavigationFragment,RotationViewModel's rotation value always alive

MainActivity

class MainActivity : AppCompatActivity() {
    lateinit var binding : ActivityMainBinding
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        binding = ActivityMainBinding.inflate(layoutInflater)
        setContentView(binding.root)
        val navHostFragment = supportFragmentManager
            .findFragmentById(binding.navHostFragment.id) as NavHostFragment
        val navController = navHostFragment.navController
        val configuration = AppBarConfiguration.Builder(binding.bottomNavigationView.menu).build()
        NavigationUI.setupActionBarWithNavController(this, navController,configuration)
        NavigationUI.setupWithNavController(binding.bottomNavigationView, navController)
    }
}

RotationFragment

When image clicking，after rotation value add 100，use animator rotation image and save (rotation+100) to ViewModel rotation value,but,after switch ScaleFragment,back to RotationFragment RotationViewModel's rotation is 100 not 0

class RotationFragment : Fragment() {
    private lateinit var viewBinding : RotationFragmentBinding

    override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {
        viewBinding = RotationFragmentBinding.inflate(inflater, container, false)
        return viewBinding.root
    }


    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
        val viewModel = ViewModelProvider(this).get(RotationViewModel::class.java)
        //viewBinding.imgRotationMood.rotation = viewModel.rotation.toFloat()
        Log.d("onViewCreated", "onViewCreated: ${viewModel.rotation.toFloat()}")
        val animatorMood = ObjectAnimator.ofFloat(viewBinding.imgRotationMood, "rotation", 0.0f,0.0f)
        animatorMood.duration = 500
        viewBinding.imgRotationMood.setOnClickListener {
            if(!animatorMood.isRunning) {
                animatorMood.setFloatValues(viewBinding.imgRotationMood.rotation,
                    viewBinding.imgRotationMood.rotation + 100)
                viewModel.rotation = viewModel.rotation + 100
                animatorMood.start()
            }
        }
    }
}

RotationViewModel

class RotationViewModel : ViewModel() {
    var rotation = 0
}

I trying use official BottomNavigation Template,get same result