Burnout -- the lassitude and loss of interest people tend to feel when they've "given it their all" within a given time frame and didn't arrive quite where they anticipated -- can happen to anyone when reality doesn't exactly line up with their expectations, and organists are not somehow immune to this.
Fierce determination to never stop playing, no matter what, is a very commendable and greatly desired quality in an organist, but, at the same time, it's also important to maintain a sense of perspective, to set realistic goals for ourselves, and pick our own battles with respect to what and in what order we learn new repertoire [See blog, Balance In Organ Playing, Part III].
One can be a very capable organist, a sensitive artist, an inspired interpreter, an imaginative improviser, and even a composer of genius -- any or all of the above -- without ever having successfully reproduced some incredible feat of musicianship which few others in history have ever attempted.
Just because we may not be among the very few who have ever recorded or performed the complete organ works of J.S. Bach in a series of recitals, for example, does not mean that we need to pursue that objective to prove to the world that we're a solid musician and capable performer.
No matter what our current level of organ playing proficiency may be, we do not have to be what society might define as "a great musician" in order for the Giver of all good gifts and graces to use our gifts -- such as they are, and just as they are -- in a great way.