In electrical engineering, we obtain maximum average power from a source with some internal impedance when the connected load impedance equals the complex conjugate of the internal source impedance. This is known by the maximum power transfer theorem. Applying this theorem means that the best we can do is to distribute the source power equally between the source internal impedance and the load impedance; i.e. the efficiency is 50%. Efficiency takes into account the ratio of the dissipated power in the load divided by the source power, on the other hand the maximum power transfer considers only the magnitude of the dissipated power. If we increase the resistance of the load more than the internal resistance of the source then we will achieve better efficiency, however the magnitude of the dissipated power will be less since the total resistance in the circuit increased. We will try to emphasize this fact in antenna problems and show that considering efficiency is more appropriate than considering maximum power transfer. Analysis is performed on half wave dipole to show that maximum power transfer impedance matching is not the optimum solution in terms of efficiency.