[Discussion moved to NotInventedHere]
The common and often mistaken belief that something you invent (design, program) yourself is better than what others have invented.
[Cynicism: For example, sufferers would often prefer to learn to play music rather than simply buying recordings of excellent performances.]
Maybe a better analogy: Sufferers would often prefer to get paid while learning to play music instead of getting paid while picking up a few CDs...
Unless the reason for learning to play music is that the process of learning (or the process of playing music) does GoodThings? that the process of listening to music doesn't.
See: NotInventedHere
Contrast: InventedHereSyndrome