Orbital hybridization is useful ibecause it can describe the shape of a molecule as well as the type of bonding in the molecule.
Hybridized orbitals are useful in explaining the shapes of and types of bonding in molecules.
For example, we can use orbital hybridization to understand why methane has the formula CH₄, how the overlap of carbon and hydrogen atomic orbitals is used to form electron-pair bonds, and why the arrangement of the C-H bonds about the central carbon is tetrahedral.
Once we know the shapes of molecules, we can predict their polarities. These in turn determine other physical properties such as melting point, boiling point, and solubility in polar and nonpolar solvents.