Gain Equation:

Gain = base × (1 + k × BiasAngle)

Pseudo-case: If base = 1000, k = 0.12, and BiasAngle = 10°,
then Gain = 1000 × (1 + 0.12 × 10) = 1000 × 2.2 = 2200

Why does more bouncing mean higher gain?
Each time an electron hits the channel wall, it can release more electrons through a process called secondary emission. More bounces mean more opportunities for multiplication, so the total number of electrons (the gain) increases as the electron path gets longer and hits the wall more frequently.