MTTs and cash games are very different formats. They are both very viable in today’s poker climate, but it’s best to choose one discipline and excel at it. That choice depends on a variety of factors, both personal and environmental. This is a very important decision in one’s poker career, so don’t take it lightly.
For most players, the choice will boil down to game availability, skill set, schedule flexibility, bankroll, and stomach for variance. Tournaments are boom and bust, with huge rewards and long dry spells. Cash games are flexible and consistent, but rarely result in accolades or big scores. For some people, it really is just a matter of preference.