What is the primary factor that defines a supergiant star's high rate of fuel consumption?

Answer

Immense internal pressures and temperatures driven by great gravity

Due to their immense gravity, the internal pressures and temperatures inside a supergiant are far greater than in smaller stars, which drives nuclear fusion reactions much faster.

What is the primary factor that defines a supergiant star's high rate of fuel consumption?
Elementhydrogencompositionstarsupergiant