Why aren't all compounds made by sharing electrons?

Not all compounds are formed by sharing electrons because some interactions involve the transfer of electrons rather than sharing. Ionic compounds, for example, are formed when one atom donates electrons to another, resulting in charged ions that attract each other. Additionally, some compounds may involve metallic bonding, where electrons are pooled and shared among a lattice of metal atoms rather than being localized between specific pairs of atoms. These different bonding mechanisms lead to a wide variety of chemical compounds with distinct properties.