How to reproduce:
1. Create new or open an existing project
2. Add a Quad 3D Object to the Scene
3. Add Cloth component
4. Start editing Cloth constraints and set all to 0
5. Start Play mode
6. Check Console and Skinned Mesh bounds in Inspector
7. Exit Play mode and start editing Cloth constraints again

Expected result: Skinned Mesh bounds do not change, can continue editing constraints
Actual result: All Skinned Mesh bound values become NaN, bounding box errors are thrown in Edit mode, Scene view becomes blank after starting editing Cloth constraints again

Reproducible with: 2017.4.38f1, 2018.4.19f1, 2019.3.6f1, 2020.1.0b2, 2020.2.0a3