How does a massive star's lifespan compare to a low-mass star on the Main Sequence?

Massive stars have shorter lifespans because they burn fuel faster.

Although it seems counterintuitive, the lifespan of a star on the Main Sequence is inversely related to its initial mass. A more massive star possesses significantly greater gravitational pressure exerted upon its core. To counteract this much higher crushing force and maintain hydrostatic equilibrium, the core temperature and density must be dramatically increased, forcing the star to consume its core hydrogen fuel at a vastly accelerated rate. Consequently, these massive, luminous, and often blue stars might only last for a few million years. In contrast, low-mass stars, such as a Red Dwarf, which is defined as having less than $0.5 M_{\odot}$, conserve their fuel so efficiently that their stable burning phase can extend for trillions of years, surpassing the current age of the universe.