Here is a good quote from Kent and Barbara Hughes’ Liberating Ministry from the Success Syndrome:

We are aware that it is possible to suppose that by refusing to quantify success (as for example, by size of congregation and staff, or numbers of souls won, or books in print, or degrees, or breadth of influence and prestige) we are encouraging mediocrity.

Far from it! Instead, think of what it would mean if we were faithful, living in profound obedience to God’s Word and working long and hard at our tasks; serving with a foot-washing heart; loving God with all our heart, soul, and might; believing what we believe; praying with the dependence and passion of Christ; living pure holy lives in this sensual world; manifesting a positive, supportive attitude in the midst of difficulties! If that is mediocrity, then give us more of this blessed mediocrity – for it is success! (p. 111)