$$ k = \frac{\frac{Q}{t}}{A(\frac{T_1 - T_2}{L})} $$
where k is thermal conductivity of the solid, Q is total amount of heat transferred, t is time taken for the heat transfer, A is area of the cross section, L is the length of the solid and T1 and T2 are the temperatures at the hotter end and the colder end respectively.
According to this formula, when a metal rod is getting heated through conduction, the temperature gradient $$\frac{T_1 - T_2}{L}$$ decides what the temperature will be at different points down the length. However, physics also states that when heat transfer takes place, it goes on until the temperature of the hotter object and the cooler object becomes equal. So, how can heat conduction stop before temperature becomes the same throughout the length of the metal rod without contradicting the basic theory of heat transfer?