The bible likens the preaching work to a sacrifice of praise - praise to God. Pioneering is also a sacrifice that involves praise. It's the sacrifice of a specified number of hours that wins you the praise of men.
When you really analyze the psychology of pioneering it is apparent that the praise of men or prominence before men is at the heart of it. Why else does the Kingdom Ministry dangle the carrot of pioneering as if it were a much to be coveted end in and of itself? Notice this excerpt from the February 2001 Our Kingdom Ministry page 3 paragraph 3:
March has five Saturdays, and April has five Sundays. By planning full service days on the weekends, many publishers who work full-time have found that auxiliary pioneering is within their reach.
Look for months with five weekends so that the coveted role of pioneer may be within your reach. Look for every possible advantage so that you can have the prominent role of pioneer. Because being a pioneer is what preaching should be all about, right? I mean who is going to preach for 70 or more hours if their name isn't going to be read from the platform at the meeting? Who is going to waste a good 70 hours preaching without getting the coveted title of pioneer?
Now think about it: what's the difference between just giving your best in the ministry and winding up preaching for 72 hours at the end of the month; and signing up to be a pioneer and preaching for 70 hours in the first 3 weeks in the month and taking the last week off because you have "made your hours"?
In the latter case you get a prominent title, a special text book and special meetings all of which are not afforded to non-pioneers - even if they made the same number of hours or more. (Not that the Service Overseer is likely to allow a publisher to make pioneer hours without harrassing him to sign up as a pioneer to make the congregation stats (specifically the number of pioneers) look good) Also, in the latter case, its not so much about doing your best than it is about "making hours" to maintain a priviledged position.
So pioneering is really a system of paying for prominence - paying for "narcissistic supply". The JW pays the organization with 70 hours of service and the organization rewards him with the prominent role of pioneer along with the perks that go along with it.
But wait a minute! Isn't seeking prominence a 'worldly' trait? So how could Jehovah's pure, spiritual, separate-from-the-world Organization have set up a system to motivate increased time publishing its message by pandering to 'worldly' traits like the desire for prominence and recognition? And didn't Jesus say not to practice your righteousness before men to have them praise you?
And don't forget the 'widow's mite'. The one giving little out of his want is giving more than the one giving a lot out of his surplus. So retired, on-vacation, unemployed or otherwise time-endowed JWs who can give a surplus of hours for the title of pioneer are, from Jehovah's standpoint, giving less than time-constrained JWs who can barely scrape 6 hours a month out of their want. But the pioneers are given the special recognition and perks while those giving time out of their want and falling below the average are considered as less spiritual.
Jesus must be very proud of his 'faithful and discreet slave'.