Why are HF scatter signals in the skip zone usually weak?
Only a small part of the signal energy is scattered into the skip zone✓Correct answer
Signals are scattered from the magnetosphere, which is not a good reflector
Propagation is via ground waves, which absorb most of the signal energy
Propagation is via ducts in the F region, which absorb most of the energy
Explanation
Scatter is an inefficient mechanism: irregularities redirect only a small fraction of the incident energy in any one direction, and the fraction aimed into the skip zone is smaller still. What arrives is therefore weak even when the transmitter is running full power.