Pretty common problem, especially on lower-end models. Fuel hoses get brittle secondary to gasoline additives and eventually crack, carb sucks air, less fuel makes it to the carb, and that is that. Drain your tanks when not in use, start it up and run it dry. Avoid ethanol blends and instead use pure gasoline blends. Also, keep an extra on hand. Seriously, extra bar, chains, files, primer bulb, carb or carb kit, bar nuts, sprocket, air cleaner, plugs, etc goes a long way! Some outfits will also keep extra gas caps on board. It isn't rocket-surgery.
