Here's why:

* Electronegativity: Chlorine is much more electronegative than hydrogen. This means chlorine has a stronger pull on the shared electrons in the bond. While the bond isn't perfectly equal, it's not a full transfer of electrons like in an ionic bond.

* Polar Covalent: The unequal sharing of electrons creates a partial positive charge on hydrogen (δ+) and a partial negative charge on chlorine (δ-). This makes HCl a polar covalent molecule.

* Gaseous state: At room temperature, HCl is a gas, which is typical for covalent compounds. Ionic compounds, on the other hand, usually form solid crystals at room temperature.

In summary, while HCl exhibits some ionic character due to the electronegativity difference, it's primarily classified as a covalent compound due to the sharing of electrons and its gaseous state.