This is cognitive dissonance in action.
A Pioneer is a professional JW.
Some do it for the recognition they receive - sacrificing their personal life in order to slave for the organization. They LOVE to let you know that they are full timers. They will always share how pioneering benefits THEM personally (and their STATUS in the organization). These are organization people and love its rules, regulations JW.org - unless it messes with own personal quirkiness and lunch dates. They'll tell you how you're not up to snuff. They love their iPads, shiny new "service car" and their never ending supply of new dresses. The pioneer 'ranks' are full of these kinda people.
Some do it because it's their life calling. These pioneers REALLY believe and follow the rule book wholeheartedly. They have come to the conclusion that their time is being controlled by Jah, Jesus and holy spirit. This type thinks they are sacrificing their lives to serve God. They are the 'old school' pioneers - live on beans and rice, work just enough to make ends meet, wear hand-me-down clothes, have yard sale furniture and a crappy car. Not many of these pioneers around anymore.