What happens to the radiation pattern of an unterminated long wire antenna as the wire length is increased?
Why A long wire carries standing waves of current with alternating phase every half wavelength. As you add more half-wave sections, the radiation from each section combines into more lobes, and the main lobes swing closer to the axis of the wire. A half-wave dipole radiates broadside, but by the time a wire is several wavelengths long the strongest lobes are only a modest angle off the wire itself, which is why long wires are aimed by pointing an end toward the target.
Watch out The idea that lobes get fewer and swing broadside is exactly backwards; broadside radiation is the behavior of a short wire near a half wavelength, and longer wires break that pattern up into many lobes.
Longer wire, more lobes, and they lean toward the wire: aim a long wire by its ends, not its sides.