Why is it not possible to downgrade the disk size for KVM VPS in SolusVM?

Question 

Why is it not possible to downgrade the disk size for KVM VPS in SolusVM?

Upon attempt to downgrade there is an error in SolusVM:

SVM_ERROR: Hdd space must be more than current, you can only upgrade 

Answer

This is expected behavior. Restriction for downgrade has been made in order to avoid a data loss on the VPS.